Merge 21d9c6330d into sapling-pr-archive-bolinfest

codex-rs/.cargo/config.toml

@@ -1,11 +1,11 @@
 [target.'cfg(all(windows, target_env = "msvc"))']
-rustflags = [
-    "-C",
-    "link-arg=/STACK:8388608",
-    "-C",
-    "llvm-args=-function-sections",
-]
+rustflags = ["-C", "link-arg=/STACK:8388608"]
 
+# MSVC emits a warning about code that may trip "Cortex-A53 MPCore processor bug #843419" (see
+# https://developer.arm.com/documentation/epm048406/latest) which is sometimes emitted by LLVM.
+# Since Arm64 Windows 10+ isn't supported on that processor, it's safe to disable the warning.
+[target.aarch64-pc-windows-msvc]
+rustflags = ["-C", "link-arg=/STACK:8388608", "-C", "link-arg=/arm64hazardfree"]
 
 [target.'cfg(all(windows, target_env = "gnu"))']
 rustflags = ["-C", "link-arg=-Wl,--stack,8388608"]

codex-rs/Cargo.lock

@@ -2400,6 +2400,7 @@ dependencies = [
  "codex-utils-pty",
  "codex-utils-sandbox-summary",
  "codex-utils-sleep-inhibitor",
+ "codex-utils-string",
  "codex-windows-sandbox",
  "color-eyre",
  "cpal",

codex-rs/Cargo.toml

@@ -118,8 +118,8 @@ codex-shell-command = { path = "shell-command" }
 codex-shell-escalation = { path = "shell-escalation" }
 codex-skills = { path = "skills" }
 codex-state = { path = "state" }
-codex-test-macros = { path = "test-macros" }
 codex-stdio-to-uds = { path = "stdio-to-uds" }
+codex-test-macros = { path = "test-macros" }
 codex-tui = { path = "tui" }
 codex-utils-absolute-path = { path = "utils/absolute-path" }
 codex-utils-approval-presets = { path = "utils/approval-presets" }
@@ -137,8 +137,8 @@ codex-utils-readiness = { path = "utils/readiness" }
 codex-utils-rustls-provider = { path = "utils/rustls-provider" }
 codex-utils-sandbox-summary = { path = "utils/sandbox-summary" }
 codex-utils-sleep-inhibitor = { path = "utils/sleep-inhibitor" }
-codex-utils-string = { path = "utils/string" }
 codex-utils-stream-parser = { path = "utils/stream-parser" }
+codex-utils-string = { path = "utils/string" }
 codex-windows-sandbox = { path = "windows-sandbox-rs" }
 core_test_support = { path = "core/tests/common" }
 mcp_test_support = { path = "mcp-server/tests/common" }
@@ -165,8 +165,8 @@ clap = "4"
 clap_complete = "4"
 color-eyre = "0.6.3"
 crossbeam-channel = "0.5.15"
-csv = "1.3.1"
 crossterm = "0.28.1"
+csv = "1.3.1"
 ctor = "0.6.3"
 derive_more = "2"
 diffy = "0.4.2"
@@ -178,8 +178,8 @@ env-flags = "0.1.1"
 env_logger = "0.11.9"
 eventsource-stream = "0.2.3"
 futures = { version = "0.3", default-features = false }
-globset = "0.4"
 gethostname = "1.1.0"
+globset = "0.4"
 http = "1.3.1"
 icu_decimal = "2.1"
 icu_locale_core = "2.1"
@@ -258,6 +258,7 @@ starlark = "0.13.0"
 strum = "0.27.2"
 strum_macros = "0.27.2"
 supports-color = "3.0.2"
+syntect = "5"
 sys-locale = "0.3.2"
 tempfile = "3.23.0"
 test-log = "0.2.19"
@@ -282,7 +283,6 @@ tracing-subscriber = "0.3.22"
 tracing-test = "0.2.5"
 tree-sitter = "0.25.10"
 tree-sitter-bash = "0.25"
-syntect = "5"
 ts-rs = "11"
 tungstenite = { version = "0.27.0", features = ["deflate", "proxy"] }
 uds_windows = "1.1.0"
@@ -352,6 +352,7 @@ ignored = [
 
 [profile.release]
 lto = "fat"
+split-debuginfo = "off"
 # Because we bundle some of these executables with the TypeScript CLI, we
 # remove everything to make the binary as small as possible.
 strip = "symbols"

codex-rs/app-server-protocol/src/protocol/v1.rs

@@ -531,6 +531,15 @@ impl From<V1TextElement> for CoreTextElement {
     }
 }
 
+impl InputItem {
+    pub fn text_char_count(&self) -> usize {
+        match self {
+            InputItem::Text { text, .. } => text.chars().count(),
+            InputItem::Image { .. } | InputItem::LocalImage { .. } => 0,
+        }
+    }
+}
+
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, JsonSchema, TS)]
 #[serde(rename_all = "camelCase")]
 /// Deprecated in favor of AccountLoginCompletedNotification.

codex-rs/app-server-protocol/src/protocol/v2.rs

@@ -3052,6 +3052,18 @@ impl From<CoreUserInput> for UserInput {
     }
 }
 
+impl UserInput {
+    pub fn text_char_count(&self) -> usize {
+        match self {
+            UserInput::Text { text, .. } => text.chars().count(),
+            UserInput::Image { .. }
+            | UserInput::LocalImage { .. }
+            | UserInput::Skill { .. }
+            | UserInput::Mention { .. } => 0,
+        }
+    }
+}
+
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, JsonSchema, TS)]
 #[serde(tag = "type", rename_all = "camelCase")]
 #[ts(tag = "type")]

codex-rs/app-server/src/codex_message_processor.rs

@@ -1,5 +1,7 @@
 use crate::bespoke_event_handling::apply_bespoke_event_handling;
+use crate::error_code::INPUT_TOO_LARGE_ERROR_CODE;
 use crate::error_code::INTERNAL_ERROR_CODE;
+use crate::error_code::INVALID_PARAMS_ERROR_CODE;
 use crate::error_code::INVALID_REQUEST_ERROR_CODE;
 use crate::fuzzy_file_search::FuzzyFileSearchSession;
 use crate::fuzzy_file_search::run_fuzzy_file_search;
@@ -267,6 +269,7 @@ use codex_protocol::protocol::RolloutItem;
 use codex_protocol::protocol::SessionConfiguredEvent;
 use codex_protocol::protocol::SessionMetaLine;
 use codex_protocol::protocol::USER_MESSAGE_BEGIN;
+use codex_protocol::user_input::MAX_USER_INPUT_TEXT_CHARS;
 use codex_protocol::user_input::UserInput as CoreInputItem;
 use codex_rmcp_client::perform_oauth_login_return_url;
 use codex_utils_json_to_toml::json_to_toml;
@@ -4735,6 +4738,36 @@ impl CodexMessageProcessor {
         self.outgoing.send_error(request_id, error).await;
     }
 
+    fn input_too_large_error(actual_chars: usize) -> JSONRPCErrorError {
+        JSONRPCErrorError {
+            code: INVALID_PARAMS_ERROR_CODE,
+            message: format!(
+                "Input exceeds the maximum length of {MAX_USER_INPUT_TEXT_CHARS} characters."
+            ),
+            data: Some(serde_json::json!({
+                "input_error_code": INPUT_TOO_LARGE_ERROR_CODE,
+                "max_chars": MAX_USER_INPUT_TEXT_CHARS,
+                "actual_chars": actual_chars,
+            })),
+        }
+    }
+
+    fn validate_v1_input_limit(items: &[WireInputItem]) -> Result<(), JSONRPCErrorError> {
+        let actual_chars: usize = items.iter().map(WireInputItem::text_char_count).sum();
+        if actual_chars > MAX_USER_INPUT_TEXT_CHARS {
+            return Err(Self::input_too_large_error(actual_chars));
+        }
+        Ok(())
+    }
+
+    fn validate_v2_input_limit(items: &[V2UserInput]) -> Result<(), JSONRPCErrorError> {
+        let actual_chars: usize = items.iter().map(V2UserInput::text_char_count).sum();
+        if actual_chars > MAX_USER_INPUT_TEXT_CHARS {
+            return Err(Self::input_too_large_error(actual_chars));
+        }
+        Ok(())
+    }
+
     async fn send_internal_error(&self, request_id: ConnectionRequestId, message: String) {
         let error = JSONRPCErrorError {
             code: INTERNAL_ERROR_CODE,
@@ -5034,6 +5067,10 @@ impl CodexMessageProcessor {
             conversation_id,
             items,
         } = params;
+        if let Err(error) = Self::validate_v1_input_limit(&items) {
+            self.outgoing.send_error(request_id, error).await;
+            return;
+        }
         let Ok(conversation) = self.thread_manager.get_thread(conversation_id).await else {
             let error = JSONRPCErrorError {
                 code: INVALID_REQUEST_ERROR_CODE,
@@ -5085,6 +5122,10 @@ impl CodexMessageProcessor {
             summary,
             output_schema,
         } = params;
+        if let Err(error) = Self::validate_v1_input_limit(&items) {
+            self.outgoing.send_error(request_id, error).await;
+            return;
+        }
 
         let Ok(conversation) = self.thread_manager.get_thread(conversation_id).await else {
             let error = JSONRPCErrorError {
@@ -5567,6 +5608,10 @@ impl CodexMessageProcessor {
     }
 
     async fn turn_start(&self, request_id: ConnectionRequestId, params: TurnStartParams) {
+        if let Err(error) = Self::validate_v2_input_limit(&params.input) {
+            self.outgoing.send_error(request_id, error).await;
+            return;
+        }
         let (_, thread) = match self.load_thread(&params.thread_id).await {
             Ok(v) => v,
             Err(error) => {
@@ -5672,6 +5717,10 @@ impl CodexMessageProcessor {
             .await;
             return;
         }
+        if let Err(error) = Self::validate_v2_input_limit(&params.input) {
+            self.outgoing.send_error(request_id, error).await;
+            return;
+        }
 
         let mapped_items: Vec<CoreInputItem> = params
             .input
@@ -7578,7 +7627,7 @@ mod tests {
                 "role": "user",
                 "content": [{
                     "type": "input_text",
-                    "text": "<user_instructions>\n<AGENTS.md contents>\n</user_instructions>".to_string(),
+                    "text": "# AGENTS.md instructions for project\n\n<INSTRUCTIONS>\n<AGENTS.md contents>\n</INSTRUCTIONS>".to_string(),
                 }],
             }),
             json!({

codex-rs/app-server/src/error_code.rs

@@ -1,3 +1,5 @@
 pub(crate) const INVALID_REQUEST_ERROR_CODE: i64 = -32600;
+pub const INVALID_PARAMS_ERROR_CODE: i64 = -32602;
 pub(crate) const INTERNAL_ERROR_CODE: i64 = -32603;
 pub(crate) const OVERLOADED_ERROR_CODE: i64 = -32001;
+pub const INPUT_TOO_LARGE_ERROR_CODE: &str = "input_too_large";

codex-rs/app-server/src/lib.rs

@@ -67,6 +67,8 @@ mod thread_state;
 mod thread_status;
 mod transport;
 
+pub use crate::error_code::INPUT_TOO_LARGE_ERROR_CODE;
+pub use crate::error_code::INVALID_PARAMS_ERROR_CODE;
 pub use crate::transport::AppServerTransport;
 
 const LOG_FORMAT_ENV_VAR: &str = "LOG_FORMAT";

codex-rs/app-server/tests/common/models_cache.rs

@@ -1,6 +1,7 @@
 use chrono::DateTime;
 use chrono::Utc;
 use codex_core::test_support::all_model_presets;
+use codex_protocol::config_types::ReasoningSummary;
 use codex_protocol::openai_models::ConfigShellToolType;
 use codex_protocol::openai_models::ModelInfo;
 use codex_protocol::openai_models::ModelPreset;
@@ -30,6 +31,7 @@ fn preset_to_info(preset: &ModelPreset, priority: i32) -> ModelInfo {
         base_instructions: "base instructions".to_string(),
         model_messages: None,
         supports_reasoning_summaries: false,
+        default_reasoning_summary: ReasoningSummary::Auto,
         support_verbosity: false,
         default_verbosity: None,
         apply_patch_tool_type: None,

codex-rs/app-server/tests/suite/output_schema.rs

@@ -1,8 +1,11 @@
 use anyhow::Result;
 use app_test_support::McpProcess;
 use app_test_support::to_response;
+use codex_app_server::INPUT_TOO_LARGE_ERROR_CODE;
+use codex_app_server::INVALID_PARAMS_ERROR_CODE;
 use codex_app_server_protocol::AddConversationListenerParams;
 use codex_app_server_protocol::InputItem;
+use codex_app_server_protocol::JSONRPCError;
 use codex_app_server_protocol::JSONRPCResponse;
 use codex_app_server_protocol::NewConversationParams;
 use codex_app_server_protocol::NewConversationResponse;
@@ -13,6 +16,7 @@ use codex_protocol::config_types::ReasoningSummary;
 use codex_protocol::openai_models::ReasoningEffort;
 use codex_protocol::protocol::AskForApproval;
 use codex_protocol::protocol::SandboxPolicy;
+use codex_protocol::user_input::MAX_USER_INPUT_TEXT_CHARS;
 use core_test_support::responses;
 use core_test_support::skip_if_no_network;
 use pretty_assertions::assert_eq;
@@ -124,6 +128,85 @@ async fn send_user_turn_accepts_output_schema_v1() -> Result<()> {
     Ok(())
 }
 
+#[tokio::test]
+async fn send_user_turn_rejects_oversized_input_v1() -> Result<()> {
+    let server = responses::start_mock_server().await;
+    let body = responses::sse(vec![
+        responses::ev_response_created("resp-1"),
+        responses::ev_assistant_message("msg-1", "Done"),
+        responses::ev_completed("resp-1"),
+    ]);
+    let _response_mock = responses::mount_sse_once(&server, body).await;
+
+    let codex_home = TempDir::new()?;
+    create_config_toml(codex_home.path(), &server.uri())?;
+
+    let mut mcp = McpProcess::new(codex_home.path()).await?;
+    timeout(DEFAULT_READ_TIMEOUT, mcp.initialize()).await??;
+
+    let new_conv_id = mcp
+        .send_new_conversation_request(NewConversationParams {
+            ..Default::default()
+        })
+        .await?;
+    let new_conv_resp: JSONRPCResponse = timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_response_message(RequestId::Integer(new_conv_id)),
+    )
+    .await??;
+    let NewConversationResponse {
+        conversation_id, ..
+    } = to_response::<NewConversationResponse>(new_conv_resp)?;
+
+    let listener_id = mcp
+        .send_add_conversation_listener_request(AddConversationListenerParams {
+            conversation_id,
+            experimental_raw_events: false,
+        })
+        .await?;
+    timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_response_message(RequestId::Integer(listener_id)),
+    )
+    .await??;
+
+    let oversized_input = "x".repeat(MAX_USER_INPUT_TEXT_CHARS + 1);
+    let send_turn_id = mcp
+        .send_send_user_turn_request(SendUserTurnParams {
+            conversation_id,
+            items: vec![InputItem::Text {
+                text: oversized_input.clone(),
+                text_elements: Vec::new(),
+            }],
+            cwd: codex_home.path().to_path_buf(),
+            approval_policy: AskForApproval::Never,
+            sandbox_policy: SandboxPolicy::DangerFullAccess,
+            model: "mock-model".to_string(),
+            effort: Some(ReasoningEffort::Low),
+            summary: ReasoningSummary::Auto,
+            output_schema: None,
+        })
+        .await?;
+
+    let err: JSONRPCError = timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_error_message(RequestId::Integer(send_turn_id)),
+    )
+    .await??;
+
+    assert_eq!(err.error.code, INVALID_PARAMS_ERROR_CODE);
+    assert_eq!(
+        err.error.message,
+        format!("Input exceeds the maximum length of {MAX_USER_INPUT_TEXT_CHARS} characters.")
+    );
+    let data = err.error.data.expect("expected structured error data");
+    assert_eq!(data["input_error_code"], INPUT_TOO_LARGE_ERROR_CODE);
+    assert_eq!(data["max_chars"], MAX_USER_INPUT_TEXT_CHARS);
+    assert_eq!(data["actual_chars"], oversized_input.chars().count());
+
+    Ok(())
+}
+
 #[tokio::test]
 async fn send_user_turn_output_schema_is_per_turn_v1() -> Result<()> {
     skip_if_no_network!(Ok(()));

codex-rs/app-server/tests/suite/send_message.rs

@@ -3,9 +3,12 @@ use app_test_support::McpProcess;
 use app_test_support::create_fake_rollout;
 use app_test_support::rollout_path;
 use app_test_support::to_response;
+use codex_app_server::INPUT_TOO_LARGE_ERROR_CODE;
+use codex_app_server::INVALID_PARAMS_ERROR_CODE;
 use codex_app_server_protocol::AddConversationListenerParams;
 use codex_app_server_protocol::AddConversationSubscriptionResponse;
 use codex_app_server_protocol::InputItem;
+use codex_app_server_protocol::JSONRPCError;
 use codex_app_server_protocol::JSONRPCNotification;
 use codex_app_server_protocol::JSONRPCResponse;
 use codex_app_server_protocol::NewConversationParams;
@@ -27,6 +30,7 @@ use codex_protocol::protocol::RolloutItem;
 use codex_protocol::protocol::RolloutLine;
 use codex_protocol::protocol::SandboxPolicy;
 use codex_protocol::protocol::TurnContextItem;
+use codex_protocol::user_input::MAX_USER_INPUT_TEXT_CHARS;
 use core_test_support::responses;
 use pretty_assertions::assert_eq;
 use std::io::Write;
@@ -210,17 +214,13 @@ async fn test_send_message_raw_notifications_opt_in() -> Result<()> {
         })
         .await?;
 
-    let permissions = read_raw_response_item(&mut mcp, conversation_id).await;
-    assert_permissions_message(&permissions);
-
     let developer = read_raw_response_item(&mut mcp, conversation_id).await;
+    assert_permissions_message(&developer);
     assert_developer_message(&developer, "Use the test harness tools.");
 
-    let instructions = read_raw_response_item(&mut mcp, conversation_id).await;
-    assert_instructions_message(&instructions);
-
-    let environment = read_raw_response_item(&mut mcp, conversation_id).await;
-    assert_environment_message(&environment);
+    let contextual_user = read_raw_response_item(&mut mcp, conversation_id).await;
+    assert_instructions_message(&contextual_user);
+    assert_environment_message(&contextual_user);
 
     let response: JSONRPCResponse = timeout(
         DEFAULT_READ_TIMEOUT,
@@ -272,6 +272,66 @@ async fn test_send_message_session_not_found() -> Result<()> {
     Ok(())
 }
 
+#[tokio::test]
+async fn test_send_message_rejects_oversized_input() -> Result<()> {
+    let server = responses::start_mock_server().await;
+    let body = responses::sse(vec![
+        responses::ev_response_created("resp-1"),
+        responses::ev_assistant_message("msg-1", "Done"),
+        responses::ev_completed("resp-1"),
+    ]);
+    let _response_mock = responses::mount_sse_once(&server, body).await;
+
+    let codex_home = TempDir::new()?;
+    create_config_toml(codex_home.path(), &server.uri())?;
+
+    let mut mcp = McpProcess::new(codex_home.path()).await?;
+    timeout(DEFAULT_READ_TIMEOUT, mcp.initialize()).await??;
+
+    let new_conv_id = mcp
+        .send_new_conversation_request(NewConversationParams {
+            ..Default::default()
+        })
+        .await?;
+    let new_conv_resp: JSONRPCResponse = timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_response_message(RequestId::Integer(new_conv_id)),
+    )
+    .await??;
+    let NewConversationResponse {
+        conversation_id, ..
+    } = to_response::<_>(new_conv_resp)?;
+
+    let oversized_input = "x".repeat(MAX_USER_INPUT_TEXT_CHARS + 1);
+    let req_id = mcp
+        .send_send_user_message_request(SendUserMessageParams {
+            conversation_id,
+            items: vec![InputItem::Text {
+                text: oversized_input.clone(),
+                text_elements: Vec::new(),
+            }],
+        })
+        .await?;
+
+    let err: JSONRPCError = timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_error_message(RequestId::Integer(req_id)),
+    )
+    .await??;
+
+    assert_eq!(err.error.code, INVALID_PARAMS_ERROR_CODE);
+    assert_eq!(
+        err.error.message,
+        format!("Input exceeds the maximum length of {MAX_USER_INPUT_TEXT_CHARS} characters.")
+    );
+    let data = err.error.data.expect("expected structured error data");
+    assert_eq!(data["input_error_code"], INPUT_TOO_LARGE_ERROR_CODE);
+    assert_eq!(data["max_chars"], MAX_USER_INPUT_TEXT_CHARS);
+    assert_eq!(data["actual_chars"], oversized_input.chars().count());
+
+    Ok(())
+}
+
 #[tokio::test]
 async fn resume_with_model_mismatch_appends_model_switch_once() -> Result<()> {
     let server = responses::start_mock_server().await;
@@ -481,9 +541,8 @@ fn assert_permissions_message(item: &ResponseItem) {
                 false,
             )
             .into_text();
-            assert_eq!(
-                texts,
-                vec![expected.as_str()],
+            assert!(
+                texts.iter().any(|text| *text == expected),
                 "expected permissions developer message, got {texts:?}"
             );
         }
@@ -496,9 +555,8 @@ fn assert_developer_message(item: &ResponseItem, expected_text: &str) {
         ResponseItem::Message { role, content, .. } => {
             assert_eq!(role, "developer");
             let texts = content_texts(content);
-            assert_eq!(
-                texts,
-                vec![expected_text],
+            assert!(
+                texts.contains(&expected_text),
                 "expected developer instructions message, got {texts:?}"
             );
         }

codex-rs/app-server/tests/suite/v2/turn_start.rs

@@ -9,6 +9,8 @@ use app_test_support::create_mock_responses_server_sequence_unchecked;
 use app_test_support::create_shell_command_sse_response;
 use app_test_support::format_with_current_shell_display;
 use app_test_support::to_response;
+use codex_app_server::INPUT_TOO_LARGE_ERROR_CODE;
+use codex_app_server::INVALID_PARAMS_ERROR_CODE;
 use codex_app_server_protocol::ByteRange;
 use codex_app_server_protocol::ClientInfo;
 use codex_app_server_protocol::CommandExecutionApprovalDecision;
@@ -19,6 +21,7 @@ use codex_app_server_protocol::FileChangeOutputDeltaNotification;
 use codex_app_server_protocol::FileChangeRequestApprovalResponse;
 use codex_app_server_protocol::ItemCompletedNotification;
 use codex_app_server_protocol::ItemStartedNotification;
+use codex_app_server_protocol::JSONRPCError;
 use codex_app_server_protocol::JSONRPCNotification;
 use codex_app_server_protocol::JSONRPCResponse;
 use codex_app_server_protocol::PatchApplyStatus;
@@ -45,6 +48,7 @@ use codex_protocol::config_types::Personality;
 use codex_protocol::config_types::ReasoningSummary;
 use codex_protocol::config_types::Settings;
 use codex_protocol::openai_models::ReasoningEffort;
+use codex_protocol::user_input::MAX_USER_INPUT_TEXT_CHARS;
 use core_test_support::responses;
 use core_test_support::skip_if_no_network;
 use pretty_assertions::assert_eq;
@@ -223,6 +227,143 @@ async fn turn_start_emits_user_message_item_with_text_elements() -> Result<()> {
     Ok(())
 }
 
+#[tokio::test]
+async fn turn_start_accepts_text_at_limit_with_mention_item() -> Result<()> {
+    let responses = vec![create_final_assistant_message_sse_response("Done")?];
+    let server = create_mock_responses_server_sequence_unchecked(responses).await;
+
+    let codex_home = TempDir::new()?;
+    create_config_toml(
+        codex_home.path(),
+        &server.uri(),
+        "never",
+        &BTreeMap::from([(Feature::Personality, true)]),
+    )?;
+
+    let mut mcp = McpProcess::new(codex_home.path()).await?;
+    timeout(DEFAULT_READ_TIMEOUT, mcp.initialize()).await??;
+
+    let thread_req = mcp
+        .send_thread_start_request(ThreadStartParams {
+            model: Some("mock-model".to_string()),
+            ..Default::default()
+        })
+        .await?;
+    let thread_resp: JSONRPCResponse = timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_response_message(RequestId::Integer(thread_req)),
+    )
+    .await??;
+    let ThreadStartResponse { thread, .. } = to_response::<ThreadStartResponse>(thread_resp)?;
+
+    let turn_req = mcp
+        .send_turn_start_request(TurnStartParams {
+            thread_id: thread.id,
+            input: vec![
+                V2UserInput::Text {
+                    text: "x".repeat(MAX_USER_INPUT_TEXT_CHARS),
+                    text_elements: Vec::new(),
+                },
+                V2UserInput::Mention {
+                    name: "Demo App".to_string(),
+                    path: "app://demo-app".to_string(),
+                },
+            ],
+            ..Default::default()
+        })
+        .await?;
+    let turn_resp: JSONRPCResponse = timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_response_message(RequestId::Integer(turn_req)),
+    )
+    .await??;
+    let TurnStartResponse { turn } = to_response::<TurnStartResponse>(turn_resp)?;
+    assert_eq!(turn.status, TurnStatus::InProgress);
+
+    timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_notification_message("turn/completed"),
+    )
+    .await??;
+
+    Ok(())
+}
+
+#[tokio::test]
+async fn turn_start_rejects_combined_oversized_text_input() -> Result<()> {
+    let codex_home = TempDir::new()?;
+    create_config_toml(
+        codex_home.path(),
+        "http://localhost/unused",
+        "never",
+        &BTreeMap::from([(Feature::Personality, true)]),
+    )?;
+
+    let mut mcp = McpProcess::new(codex_home.path()).await?;
+    timeout(DEFAULT_READ_TIMEOUT, mcp.initialize()).await??;
+
+    let thread_req = mcp
+        .send_thread_start_request(ThreadStartParams {
+            model: Some("mock-model".to_string()),
+            ..Default::default()
+        })
+        .await?;
+    let thread_resp: JSONRPCResponse = timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_response_message(RequestId::Integer(thread_req)),
+    )
+    .await??;
+    let ThreadStartResponse { thread, .. } = to_response::<ThreadStartResponse>(thread_resp)?;
+
+    let first = "x".repeat(MAX_USER_INPUT_TEXT_CHARS / 2);
+    let second = "y".repeat(MAX_USER_INPUT_TEXT_CHARS / 2 + 1);
+    let actual_chars = first.chars().count() + second.chars().count();
+
+    let turn_req = mcp
+        .send_turn_start_request(TurnStartParams {
+            thread_id: thread.id,
+            input: vec![
+                V2UserInput::Text {
+                    text: first,
+                    text_elements: Vec::new(),
+                },
+                V2UserInput::Text {
+                    text: second,
+                    text_elements: Vec::new(),
+                },
+            ],
+            ..Default::default()
+        })
+        .await?;
+    let err: JSONRPCError = timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_error_message(RequestId::Integer(turn_req)),
+    )
+    .await??;
+
+    assert_eq!(err.error.code, INVALID_PARAMS_ERROR_CODE);
+    assert_eq!(
+        err.error.message,
+        format!("Input exceeds the maximum length of {MAX_USER_INPUT_TEXT_CHARS} characters.")
+    );
+    let data = err.error.data.expect("expected structured error data");
+    assert_eq!(data["input_error_code"], INPUT_TOO_LARGE_ERROR_CODE);
+    assert_eq!(data["max_chars"], MAX_USER_INPUT_TEXT_CHARS);
+    assert_eq!(data["actual_chars"], actual_chars);
+
+    let turn_started = tokio::time::timeout(
+        std::time::Duration::from_millis(250),
+        mcp.read_stream_until_notification_message("turn/started"),
+    )
+    .await;
+    assert!(
+        turn_started.is_err(),
+        "did not expect a turn/started notification for rejected input"
+    );
+
+    Ok(())
+}
+
 #[tokio::test]
 async fn turn_start_emits_notifications_and_accepts_model_override() -> Result<()> {
     // Provide a mock server and config so model wiring is valid.

codex-rs/app-server/tests/suite/v2/turn_steer.rs

@@ -6,6 +6,8 @@ use app_test_support::create_mock_responses_server_sequence;
 use app_test_support::create_mock_responses_server_sequence_unchecked;
 use app_test_support::create_shell_command_sse_response;
 use app_test_support::to_response;
+use codex_app_server::INPUT_TOO_LARGE_ERROR_CODE;
+use codex_app_server::INVALID_PARAMS_ERROR_CODE;
 use codex_app_server_protocol::JSONRPCError;
 use codex_app_server_protocol::JSONRPCNotification;
 use codex_app_server_protocol::JSONRPCResponse;
@@ -17,6 +19,7 @@ use codex_app_server_protocol::TurnStartResponse;
 use codex_app_server_protocol::TurnSteerParams;
 use codex_app_server_protocol::TurnSteerResponse;
 use codex_app_server_protocol::UserInput as V2UserInput;
+use codex_protocol::user_input::MAX_USER_INPUT_TEXT_CHARS;
 use tempfile::TempDir;
 use tokio::time::timeout;
 
@@ -67,6 +70,109 @@ async fn turn_steer_requires_active_turn() -> Result<()> {
     Ok(())
 }
 
+#[tokio::test]
+async fn turn_steer_rejects_oversized_text_input() -> Result<()> {
+    #[cfg(target_os = "windows")]
+    let shell_command = vec![
+        "powershell".to_string(),
+        "-Command".to_string(),
+        "Start-Sleep -Seconds 10".to_string(),
+    ];
+    #[cfg(not(target_os = "windows"))]
+    let shell_command = vec!["sleep".to_string(), "10".to_string()];
+
+    let tmp = TempDir::new()?;
+    let codex_home = tmp.path().join("codex_home");
+    std::fs::create_dir(&codex_home)?;
+    let working_directory = tmp.path().join("workdir");
+    std::fs::create_dir(&working_directory)?;
+
+    let server =
+        create_mock_responses_server_sequence_unchecked(vec![create_shell_command_sse_response(
+            shell_command.clone(),
+            Some(&working_directory),
+            Some(10_000),
+            "call_sleep",
+        )?])
+        .await;
+    create_config_toml(&codex_home, &server.uri())?;
+
+    let mut mcp = McpProcess::new(&codex_home).await?;
+    timeout(DEFAULT_READ_TIMEOUT, mcp.initialize()).await??;
+
+    let thread_req = mcp
+        .send_thread_start_request(ThreadStartParams {
+            model: Some("mock-model".to_string()),
+            ..Default::default()
+        })
+        .await?;
+    let thread_resp: JSONRPCResponse = timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_response_message(RequestId::Integer(thread_req)),
+    )
+    .await??;
+    let ThreadStartResponse { thread, .. } = to_response::<ThreadStartResponse>(thread_resp)?;
+
+    let turn_req = mcp
+        .send_turn_start_request(TurnStartParams {
+            thread_id: thread.id.clone(),
+            input: vec![V2UserInput::Text {
+                text: "run sleep".to_string(),
+                text_elements: Vec::new(),
+            }],
+            cwd: Some(working_directory.clone()),
+            ..Default::default()
+        })
+        .await?;
+    let turn_resp: JSONRPCResponse = timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_response_message(RequestId::Integer(turn_req)),
+    )
+    .await??;
+    let TurnStartResponse { turn } = to_response::<TurnStartResponse>(turn_resp)?;
+
+    let _task_started: JSONRPCNotification = timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_notification_message("codex/event/task_started"),
+    )
+    .await??;
+
+    let oversized_input = "x".repeat(MAX_USER_INPUT_TEXT_CHARS + 1);
+    let steer_req = mcp
+        .send_turn_steer_request(TurnSteerParams {
+            thread_id: thread.id.clone(),
+            input: vec![V2UserInput::Text {
+                text: oversized_input.clone(),
+                text_elements: Vec::new(),
+            }],
+            expected_turn_id: turn.id.clone(),
+        })
+        .await?;
+    let steer_err: JSONRPCError = timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_error_message(RequestId::Integer(steer_req)),
+    )
+    .await??;
+
+    assert_eq!(steer_err.error.code, INVALID_PARAMS_ERROR_CODE);
+    assert_eq!(
+        steer_err.error.message,
+        format!("Input exceeds the maximum length of {MAX_USER_INPUT_TEXT_CHARS} characters.")
+    );
+    let data = steer_err
+        .error
+        .data
+        .expect("expected structured error data");
+    assert_eq!(data["input_error_code"], INPUT_TOO_LARGE_ERROR_CODE);
+    assert_eq!(data["max_chars"], MAX_USER_INPUT_TEXT_CHARS);
+    assert_eq!(data["actual_chars"], oversized_input.chars().count());
+
+    mcp.interrupt_turn_and_wait_for_aborted(thread.id, turn.id, DEFAULT_READ_TIMEOUT)
+        .await?;
+
+    Ok(())
+}
+
 #[tokio::test]
 async fn turn_steer_returns_active_turn_id() -> Result<()> {
     #[cfg(target_os = "windows")]

codex-rs/cli/src/main.rs

@@ -808,6 +808,7 @@ async fn cli_main(arg0_paths: Arg0DispatchPaths) -> anyhow::Result<()> {
                     stage_width = stage_width.max(stage.len());
                     rows.push((name, stage, enabled));
                 }
+                rows.sort_unstable_by_key(|(name, _, _)| *name);
 
                 for (name, stage, enabled) in rows {
                     println!("{name:<name_width$}  {stage:<stage_width$}  {enabled}");

codex-rs/cli/tests/features.rs

@@ -2,6 +2,7 @@ use std::path::Path;
 
 use anyhow::Result;
 use predicates::str::contains;
+use pretty_assertions::assert_eq;
 use tempfile::TempDir;
 
 fn codex_command(codex_home: &Path) -> Result<assert_cmd::Command> {
@@ -58,3 +59,33 @@ async fn features_enable_under_development_feature_prints_warning() -> Result<()
 
     Ok(())
 }
+
+#[tokio::test]
+async fn features_list_is_sorted_alphabetically_by_feature_name() -> Result<()> {
+    let codex_home = TempDir::new()?;
+
+    let mut cmd = codex_command(codex_home.path())?;
+    let output = cmd
+        .args(["features", "list"])
+        .assert()
+        .success()
+        .get_output()
+        .stdout
+        .clone();
+    let stdout = String::from_utf8(output)?;
+
+    let actual_names = stdout
+        .lines()
+        .map(|line| {
+            line.split_once("  ")
+                .map(|(name, _)| name.trim_end().to_string())
+                .expect("feature list output should contain aligned columns")
+        })
+        .collect::<Vec<_>>();
+    let mut expected_names = actual_names.clone();
+    expected_names.sort();
+
+    assert_eq!(actual_names, expected_names);
+
+    Ok(())
+}

codex-rs/codex-api/tests/models_integration.rs

@@ -3,6 +3,7 @@ use codex_api::ModelsClient;
 use codex_api::provider::Provider;
 use codex_api::provider::RetryConfig;
 use codex_client::ReqwestTransport;
+use codex_protocol::config_types::ReasoningSummary;
 use codex_protocol::openai_models::ConfigShellToolType;
 use codex_protocol::openai_models::ModelInfo;
 use codex_protocol::openai_models::ModelVisibility;
@@ -78,6 +79,7 @@ async fn models_client_hits_models_endpoint() {
             base_instructions: "base instructions".to_string(),
             model_messages: None,
             supports_reasoning_summaries: false,
+            default_reasoning_summary: ReasoningSummary::Auto,
             support_verbosity: false,
             default_verbosity: None,
             apply_patch_tool_type: None,

codex-rs/core/config.schema.json

@@ -630,6 +630,11 @@
           "minimum": 0.0,
           "type": "integer"
         },
+        "max_unused_days": {
+          "description": "Maximum number of days since a memory was last used before it becomes ineligible for phase 2 selection.",
+          "format": "int64",
+          "type": "integer"
+        },
         "min_rollout_idle_hours": {
           "description": "Minimum idle time between last thread activity and memory creation (hours). > 12h recommended.",
           "format": "int64",

codex-rs/core/src/agent/agent_names.txt

@@ -1,87 +1,100 @@
-Ash
-Elm
-Yew
-Fir
-Oak
-Pine
-Spruce
-Cedar
-Birch
-Maple
-Beech
-Alder
-Willow
-Poplar
-Aspen
-Larch
-Juniper
-Cypress
-Hemlock
-Sequoia
-Baobab
-Acacia
-Banyan
-Teak
-Olive
-Cherry
-Apple
-Pear
-Plum
-Peach
-Mango
-Guava
-Fig
-Date
-Palm
-Holly
-Ivy
-Fern
-Moss
-Reed
-Cane
-Rush
-Sage
-Mint
-Thyme
-Basil
-Dill
-Fennel
-Parsley
-Laurel
-Myrtle
-Lotus
-Tulip
-Rose
-Daisy
-Lily
-Iris
-Poppy
-Aster
-Peony
-Camellia
-Azalea
-Begonia
-Petunia
-Verbena
-Marigold
-Daffodil
-Orchid
-Violet
-Clover
-Bamboo
-Eucalypt
-Oleander
-Yucca
-Agave
-Aloe
-Cactus
-Sedum
-Boxwood
-Hawthorn
-Redwood
-Ironwood
-Sandal
-Kapok
-Mahonia
-Spirea
-Wisteria
+Euclid
+Archimedes
+Ptolemy
+Hypatia
+Avicenna
+Averroes
+Aquinas
+Copernicus
+Kepler
+Galileo
+Bacon
+Descartes
+Pascal
+Fermat
+Huygens
+Leibniz
+Newton
+Halley
+Euler
+Lagrange
+Laplace
+Volta
+Gauss
+Ampere
+Faraday
+Darwin
+Lovelace
+Boole
+Pasteur
+Maxwell
+Mendel
+Curie
+Planck
+Tesla
+Poincare
+Noether
+Hilbert
+Einstein
+Raman
+Bohr
+Turing
+Hubble
+Feynman
+Franklin
+McClintock
+Meitner
+Herschel
+Linnaeus
+Wegener
+Chandrasekhar
+Sagan
+Goodall
+Carson
+Carver
+Socrates
+Plato
+Aristotle
+Epicurus
+Cicero
+Confucius
+Mencius
+Zeno
+Locke
+Hume
+Kant
+Hegel
+Kierkegaard
+Mill
+Nietzsche
+Peirce
+James
+Dewey
+Russell
+Popper
+Sartre
+Beauvoir
+Arendt
+Rawls
+Singer
+Anscombe
+Parfit
+Kuhn
+Boyle
+Hooke
+Harvey
+Dalton
+Ohm
+Helmholtz
+Gibbs
+Lorentz
+Schrodinger
+Heisenberg
+Pauli
+Dirac
+Bernoulli
+Godel
+Nash
+Banach
+Ramanujan
+Erdos

codex-rs/core/src/agent/control.rs

@@ -4,11 +4,17 @@ use crate::agent::status::is_final;
 use crate::error::CodexErr;
 use crate::error::Result as CodexResult;
 use crate::find_thread_path_by_id_str;
+use crate::rollout::RolloutRecorder;
+use crate::session_prefix::format_subagent_context_line;
 use crate::session_prefix::format_subagent_notification_message;
 use crate::state_db;
 use crate::thread_manager::ThreadManagerState;
 use codex_protocol::ThreadId;
+use codex_protocol::models::FunctionCallOutputPayload;
+use codex_protocol::models::ResponseItem;
+use codex_protocol::protocol::InitialHistory;
 use codex_protocol::protocol::Op;
+use codex_protocol::protocol::RolloutItem;
 use codex_protocol::protocol::SessionSource;
 use codex_protocol::protocol::SubAgentSource;
 use codex_protocol::protocol::TokenUsage;
@@ -18,6 +24,12 @@ use std::sync::Weak;
 use tokio::sync::watch;
 
 const AGENT_NAMES: &str = include_str!("agent_names.txt");
+const FORKED_SPAWN_AGENT_OUTPUT_MESSAGE: &str = "You are the newly spawned agent. The prior conversation history was forked from your parent agent. Treat the next user message as your new task, and use the forked history only as background context.";
+
+#[derive(Clone, Debug, Default)]
+pub(crate) struct SpawnAgentOptions {
+    pub(crate) fork_parent_spawn_call_id: Option<String>,
+}
 
 fn agent_nickname_list() -> Vec<&'static str> {
     AGENT_NAMES
@@ -57,6 +69,17 @@ impl AgentControl {
         config: crate::config::Config,
         items: Vec<UserInput>,
         session_source: Option<SessionSource>,
+    ) -> CodexResult<ThreadId> {
+        self.spawn_agent_with_options(config, items, session_source, SpawnAgentOptions::default())
+            .await
+    }
+
+    pub(crate) async fn spawn_agent_with_options(
+        &self,
+        config: crate::config::Config,
+        items: Vec<UserInput>,
+        session_source: Option<SessionSource>,
+        options: SpawnAgentOptions,
     ) -> CodexResult<ThreadId> {
         let state = self.upgrade()?;
         let mut reservation = self.state.reserve_spawn_slot(config.agent_max_threads)?;
@@ -82,9 +105,75 @@ impl AgentControl {
         // The same `AgentControl` is sent to spawn the thread.
         let new_thread = match session_source {
             Some(session_source) => {
-                state
-                    .spawn_new_thread_with_source(config, self.clone(), session_source, false, None)
-                    .await?
+                if let Some(call_id) = options.fork_parent_spawn_call_id.as_ref() {
+                    let SessionSource::SubAgent(SubAgentSource::ThreadSpawn {
+                        parent_thread_id,
+                        ..
+                    }) = session_source.clone()
+                    else {
+                        return Err(CodexErr::Fatal(
+                            "spawn_agent fork requires a thread-spawn session source".to_string(),
+                        ));
+                    };
+                    let parent_thread = state.get_thread(parent_thread_id).await.ok();
+                    if let Some(parent_thread) = parent_thread.as_ref() {
+                        // `record_conversation_items` only queues rollout writes asynchronously.
+                        // Flush/materialize the live parent before snapshotting JSONL for a fork.
+                        parent_thread
+                            .codex
+                            .session
+                            .ensure_rollout_materialized()
+                            .await;
+                        parent_thread.codex.session.flush_rollout().await;
+                    }
+                    let rollout_path = parent_thread
+                        .as_ref()
+                        .and_then(|parent_thread| parent_thread.rollout_path())
+                        .or(find_thread_path_by_id_str(
+                            config.codex_home.as_path(),
+                            &parent_thread_id.to_string(),
+                        )
+                        .await?)
+                        .ok_or_else(|| {
+                            CodexErr::Fatal(format!(
+                                "parent thread rollout unavailable for fork: {parent_thread_id}"
+                            ))
+                        })?;
+                    let mut forked_rollout_items =
+                        RolloutRecorder::get_rollout_history(&rollout_path)
+                            .await?
+                            .get_rollout_items();
+                    let mut output = FunctionCallOutputPayload::from_text(
+                        FORKED_SPAWN_AGENT_OUTPUT_MESSAGE.to_string(),
+                    );
+                    output.success = Some(true);
+                    forked_rollout_items.push(RolloutItem::ResponseItem(
+                        ResponseItem::FunctionCallOutput {
+                            call_id: call_id.clone(),
+                            output,
+                        },
+                    ));
+                    let initial_history = InitialHistory::Forked(forked_rollout_items);
+                    state
+                        .fork_thread_with_source(
+                            config,
+                            initial_history,
+                            self.clone(),
+                            session_source,
+                            false,
+                        )
+                        .await?
+                } else {
+                    state
+                        .spawn_new_thread_with_source(
+                            config,
+                            self.clone(),
+                            session_source,
+                            false,
+                            None,
+                        )
+                        .await?
+                }
             }
             None => state.spawn_new_thread(config, self.clone()).await?,
         };
@@ -255,6 +344,40 @@ impl AgentControl {
         thread.total_token_usage().await
     }
 
+    pub(crate) async fn format_environment_context_subagents(
+        &self,
+        parent_thread_id: ThreadId,
+    ) -> String {
+        let Ok(state) = self.upgrade() else {
+            return String::new();
+        };
+
+        let mut agents = Vec::new();
+        for thread_id in state.list_thread_ids().await {
+            let Ok(thread) = state.get_thread(thread_id).await else {
+                continue;
+            };
+            let snapshot = thread.config_snapshot().await;
+            let SessionSource::SubAgent(SubAgentSource::ThreadSpawn {
+                parent_thread_id: agent_parent_thread_id,
+                agent_nickname,
+                ..
+            }) = snapshot.session_source
+            else {
+                continue;
+            };
+            if agent_parent_thread_id != parent_thread_id {
+                continue;
+            }
+            agents.push(format_subagent_context_line(
+                &thread_id.to_string(),
+                agent_nickname.as_deref(),
+            ));
+        }
+        agents.sort();
+        agents.join("\n")
+    }
+
     /// Starts a detached watcher for sub-agents spawned from another thread.
     ///
     /// This is only enabled for `SubAgentSource::ThreadSpawn`, where a parent thread exists and
@@ -319,8 +442,8 @@ mod tests {
     use crate::config::Config;
     use crate::config::ConfigBuilder;
     use crate::config_loader::LoaderOverrides;
+    use crate::contextual_user_message::SUBAGENT_NOTIFICATION_OPEN_TAG;
     use crate::features::Feature;
-    use crate::session_prefix::SUBAGENT_NOTIFICATION_OPEN_TAG;
     use assert_matches::assert_matches;
     use codex_protocol::config_types::ModeKind;
     use codex_protocol::models::ContentItem;
@@ -421,6 +544,21 @@ mod tests {
         })
     }
 
+    /// Returns true when any message item contains `needle` in a text span.
+    fn history_contains_text(history_items: &[ResponseItem], needle: &str) -> bool {
+        history_items.iter().any(|item| {
+            let ResponseItem::Message { content, .. } = item else {
+                return false;
+            };
+            content.iter().any(|content_item| match content_item {
+                ContentItem::InputText { text } | ContentItem::OutputText { text } => {
+                    text.contains(needle)
+                }
+                ContentItem::InputImage { .. } => false,
+            })
+        })
+    }
+
     async fn wait_for_subagent_notification(parent_thread: &Arc<CodexThread>) -> bool {
         let wait = async {
             loop {
@@ -673,6 +811,242 @@ mod tests {
         assert_eq!(captured, Some(expected));
     }
 
+    #[tokio::test]
+    async fn spawn_agent_can_fork_parent_thread_history() {
+        let harness = AgentControlHarness::new().await;
+        let (parent_thread_id, parent_thread) = harness.start_thread().await;
+        parent_thread
+            .inject_user_message_without_turn("parent seed context".to_string())
+            .await;
+        let turn_context = parent_thread.codex.session.new_default_turn().await;
+        let parent_spawn_call_id = "spawn-call-history".to_string();
+        let parent_spawn_call = ResponseItem::FunctionCall {
+            id: None,
+            name: "spawn_agent".to_string(),
+            arguments: "{}".to_string(),
+            call_id: parent_spawn_call_id.clone(),
+        };
+        parent_thread
+            .codex
+            .session
+            .record_conversation_items(turn_context.as_ref(), &[parent_spawn_call])
+            .await;
+        parent_thread
+            .codex
+            .session
+            .ensure_rollout_materialized()
+            .await;
+        parent_thread.codex.session.flush_rollout().await;
+
+        let child_thread_id = harness
+            .control
+            .spawn_agent_with_options(
+                harness.config.clone(),
+                text_input("child task"),
+                Some(SessionSource::SubAgent(SubAgentSource::ThreadSpawn {
+                    parent_thread_id,
+                    depth: 1,
+                    agent_nickname: None,
+                    agent_role: None,
+                })),
+                SpawnAgentOptions {
+                    fork_parent_spawn_call_id: Some(parent_spawn_call_id),
+                },
+            )
+            .await
+            .expect("forked spawn should succeed");
+
+        let child_thread = harness
+            .manager
+            .get_thread(child_thread_id)
+            .await
+            .expect("child thread should be registered");
+        assert_ne!(child_thread_id, parent_thread_id);
+        let history = child_thread.codex.session.clone_history().await;
+        assert!(history_contains_text(
+            history.raw_items(),
+            "parent seed context"
+        ));
+
+        let expected = (
+            child_thread_id,
+            Op::UserInput {
+                items: vec![UserInput::Text {
+                    text: "child task".to_string(),
+                    text_elements: Vec::new(),
+                }],
+                final_output_json_schema: None,
+            },
+        );
+        let captured = harness
+            .manager
+            .captured_ops()
+            .into_iter()
+            .find(|entry| *entry == expected);
+        assert_eq!(captured, Some(expected));
+
+        let _ = harness
+            .control
+            .shutdown_agent(child_thread_id)
+            .await
+            .expect("child shutdown should submit");
+        let _ = parent_thread
+            .submit(Op::Shutdown {})
+            .await
+            .expect("parent shutdown should submit");
+    }
+
+    #[tokio::test]
+    async fn spawn_agent_fork_injects_output_for_parent_spawn_call() {
+        let harness = AgentControlHarness::new().await;
+        let (parent_thread_id, parent_thread) = harness.start_thread().await;
+        let turn_context = parent_thread.codex.session.new_default_turn().await;
+        let parent_spawn_call_id = "spawn-call-1".to_string();
+        let parent_spawn_call = ResponseItem::FunctionCall {
+            id: None,
+            name: "spawn_agent".to_string(),
+            arguments: "{}".to_string(),
+            call_id: parent_spawn_call_id.clone(),
+        };
+        parent_thread
+            .codex
+            .session
+            .record_conversation_items(turn_context.as_ref(), &[parent_spawn_call])
+            .await;
+        parent_thread
+            .codex
+            .session
+            .ensure_rollout_materialized()
+            .await;
+        parent_thread.codex.session.flush_rollout().await;
+
+        let child_thread_id = harness
+            .control
+            .spawn_agent_with_options(
+                harness.config.clone(),
+                text_input("child task"),
+                Some(SessionSource::SubAgent(SubAgentSource::ThreadSpawn {
+                    parent_thread_id,
+                    depth: 1,
+                    agent_nickname: None,
+                    agent_role: None,
+                })),
+                SpawnAgentOptions {
+                    fork_parent_spawn_call_id: Some(parent_spawn_call_id.clone()),
+                },
+            )
+            .await
+            .expect("forked spawn should succeed");
+
+        let child_thread = harness
+            .manager
+            .get_thread(child_thread_id)
+            .await
+            .expect("child thread should be registered");
+        let history = child_thread.codex.session.clone_history().await;
+        let injected_output = history.raw_items().iter().find_map(|item| match item {
+            ResponseItem::FunctionCallOutput { call_id, output }
+                if call_id == &parent_spawn_call_id =>
+            {
+                Some(output)
+            }
+            _ => None,
+        });
+        let injected_output =
+            injected_output.expect("forked child should contain synthetic tool output");
+        assert_eq!(
+            injected_output.text_content(),
+            Some(FORKED_SPAWN_AGENT_OUTPUT_MESSAGE)
+        );
+        assert_eq!(injected_output.success, Some(true));
+
+        let _ = harness
+            .control
+            .shutdown_agent(child_thread_id)
+            .await
+            .expect("child shutdown should submit");
+        let _ = parent_thread
+            .submit(Op::Shutdown {})
+            .await
+            .expect("parent shutdown should submit");
+    }
+
+    #[tokio::test]
+    async fn spawn_agent_fork_flushes_parent_rollout_before_loading_history() {
+        let harness = AgentControlHarness::new().await;
+        let (parent_thread_id, parent_thread) = harness.start_thread().await;
+        let turn_context = parent_thread.codex.session.new_default_turn().await;
+        let parent_spawn_call_id = "spawn-call-unflushed".to_string();
+        let parent_spawn_call = ResponseItem::FunctionCall {
+            id: None,
+            name: "spawn_agent".to_string(),
+            arguments: "{}".to_string(),
+            call_id: parent_spawn_call_id.clone(),
+        };
+        parent_thread
+            .codex
+            .session
+            .record_conversation_items(turn_context.as_ref(), &[parent_spawn_call])
+            .await;
+
+        let child_thread_id = harness
+            .control
+            .spawn_agent_with_options(
+                harness.config.clone(),
+                text_input("child task"),
+                Some(SessionSource::SubAgent(SubAgentSource::ThreadSpawn {
+                    parent_thread_id,
+                    depth: 1,
+                    agent_nickname: None,
+                    agent_role: None,
+                })),
+                SpawnAgentOptions {
+                    fork_parent_spawn_call_id: Some(parent_spawn_call_id.clone()),
+                },
+            )
+            .await
+            .expect("forked spawn should flush parent rollout before loading history");
+
+        let child_thread = harness
+            .manager
+            .get_thread(child_thread_id)
+            .await
+            .expect("child thread should be registered");
+        let history = child_thread.codex.session.clone_history().await;
+
+        let mut parent_call_index = None;
+        let mut injected_output_index = None;
+        for (idx, item) in history.raw_items().iter().enumerate() {
+            match item {
+                ResponseItem::FunctionCall { call_id, .. } if call_id == &parent_spawn_call_id => {
+                    parent_call_index = Some(idx);
+                }
+                ResponseItem::FunctionCallOutput { call_id, .. }
+                    if call_id == &parent_spawn_call_id =>
+                {
+                    injected_output_index = Some(idx);
+                }
+                _ => {}
+            }
+        }
+
+        let parent_call_index =
+            parent_call_index.expect("forked child should include the parent spawn_agent call");
+        let injected_output_index = injected_output_index
+            .expect("forked child should include synthetic output for the parent spawn_agent call");
+        assert!(parent_call_index < injected_output_index);
+
+        let _ = harness
+            .control
+            .shutdown_agent(child_thread_id)
+            .await
+            .expect("child shutdown should submit");
+        let _ = parent_thread
+            .submit(Op::Shutdown {})
+            .await
+            .expect("parent shutdown should submit");
+    }
+
     #[tokio::test]
     async fn spawn_agent_respects_max_threads_limit() {
         let max_threads = 1usize;

codex-rs/core/src/agent/role.rs

@@ -190,13 +190,17 @@ Rules:
                 (
                     "awaiter".to_string(),
                     AgentRoleConfig {
-                        description: Some(r#"Use an `awaiter` agent EVERY TIME you must run a command that might take some time.
+                        description: Some(r#"Use an `awaiter` agent EVERY TIME you must run a command that will take some very long time.
 This includes, but not only:
 * testing
 * monitoring of a long running process
 * explicit ask to wait for something
 
-When YOU wait for the `awaiter` agent to be done, use the largest possible timeout."#.to_string()),
+Rules:
+- When an awaiter is running, you can work on something else. If you need to wait for its completion, use the largest possible timeout.
+- Be patient with the `awaiter`.
+- Do not use an awaiter for every compilation/test if it won't take time. Only use if for long running commands.
+- Close the awaiter when you're done with it."#.to_string()),
                         config_file: Some("awaiter.toml".to_string().parse().unwrap_or_default()),
                     }
                 )

codex-rs/core/src/codex.rs

@@ -754,7 +754,7 @@ pub(crate) struct SessionConfiguration {
     provider: ModelProviderInfo,
 
     collaboration_mode: CollaborationMode,
-    model_reasoning_summary: ReasoningSummaryConfig,
+    model_reasoning_summary: Option<ReasoningSummaryConfig>,
 
     /// Developer instructions that supplement the base instructions.
     developer_instructions: Option<String>,
@@ -824,7 +824,7 @@ impl SessionConfiguration {
             next_configuration.collaboration_mode = collaboration_mode;
         }
         if let Some(summary) = updates.reasoning_summary {
-            next_configuration.model_reasoning_summary = summary;
+            next_configuration.model_reasoning_summary = Some(summary);
         }
         if let Some(personality) = updates.personality {
             next_configuration.personality = Some(personality);
@@ -985,7 +985,9 @@ impl Session {
         skills_outcome: Arc<SkillLoadOutcome>,
     ) -> TurnContext {
         let reasoning_effort = session_configuration.collaboration_mode.reasoning_effort();
-        let reasoning_summary = session_configuration.model_reasoning_summary;
+        let reasoning_summary = session_configuration
+            .model_reasoning_summary
+            .unwrap_or(model_info.default_reasoning_summary);
         let otel_manager = otel_manager.clone().with_model(
             session_configuration.collaboration_mode.model(),
             model_info.slug.as_str(),
@@ -1124,7 +1126,7 @@ impl Session {
         //
         // - initialize RolloutRecorder with new or resumed session info
         // - perform default shell discovery
-        // - load history metadata
+        // - load history metadata (skipped for subagents)
         let rollout_fut = async {
             if config.ephemeral {
                 Ok::<_, anyhow::Error>((None, None))
@@ -1141,7 +1143,16 @@ impl Session {
             }
         };
 
-        let history_meta_fut = crate::message_history::history_metadata(&config);
+        let history_meta_fut = async {
+            if matches!(
+                session_configuration.session_source,
+                SessionSource::SubAgent(_)
+            ) {
+                (0, 0)
+            } else {
+                crate::message_history::history_metadata(&config).await
+            }
+        };
         let auth_manager_clone = Arc::clone(&auth_manager);
         let config_for_mcp = Arc::clone(&config);
         let auth_and_mcp_fut = async move {
@@ -1262,7 +1273,9 @@ impl Session {
         otel_manager.conversation_starts(
             config.model_provider.name.as_str(),
             session_configuration.collaboration_mode.reasoning_effort(),
-            config.model_reasoning_summary,
+            config
+                .model_reasoning_summary
+                .unwrap_or(ReasoningSummaryConfig::Auto),
             config.model_context_window,
             config.model_auto_compact_token_limit,
             config.permissions.approval_policy.value(),
@@ -1669,7 +1682,10 @@ impl Session {
         match conversation_history {
             InitialHistory::New => {
                 // Build and record initial items (user instructions + environment context)
-                let items = self.build_initial_context(&turn_context).await;
+                // TODO(ccunningham): Defer initial context insertion until the first real turn
+                // starts so it reflects the actual first-turn settings (permissions, etc.) and
+                // we do not emit model-visible "diff" updates before the first user message.
+                let items = self.build_initial_context(&turn_context, None).await;
                 self.record_conversation_items(&turn_context, &items).await;
                 {
                     let mut state = self.state.lock().await;
@@ -1773,7 +1789,7 @@ impl Session {
                 }
 
                 // Append the current session's initial context after the reconstructed history.
-                let initial_context = self.build_initial_context(&turn_context).await;
+                let initial_context = self.build_initial_context(&turn_context, None).await;
                 self.record_conversation_items(&turn_context, &initial_context)
                     .await;
                 {
@@ -2862,7 +2878,7 @@ impl Session {
                     } else {
                         let user_messages = collect_user_messages(history.raw_items());
                         let rebuilt = compact::build_compacted_history(
-                            self.build_initial_context(turn_context).await,
+                            self.build_initial_context(turn_context, None).await,
                             &user_messages,
                             &compacted.message,
                         );
@@ -2990,10 +3006,20 @@ impl Session {
     pub(crate) async fn build_initial_context(
         &self,
         turn_context: &TurnContext,
+        previous_user_turn_model: Option<&str>,
     ) -> Vec<ResponseItem> {
-        let mut items = Vec::<ResponseItem>::with_capacity(4);
+        let mut developer_sections = Vec::<String>::with_capacity(8);
+        let mut contextual_user_sections = Vec::<String>::with_capacity(2);
         let shell = self.user_shell();
-        items.push(
+        if let Some(model_switch_message) =
+            crate::context_manager::updates::build_model_instructions_update_item(
+                previous_user_turn_model,
+                turn_context,
+            )
+        {
+            developer_sections.push(model_switch_message.into_text());
+        }
+        developer_sections.push(
             DeveloperInstructions::from_policy(
                 turn_context.sandbox_policy.get(),
                 turn_context.approval_policy.value(),
@@ -3001,17 +3027,17 @@ impl Session {
                 &turn_context.cwd,
                 turn_context.features.enabled(Feature::RequestPermissions),
             )
-            .into(),
+            .into_text(),
         );
         if let Some(developer_instructions) = turn_context.developer_instructions.as_deref() {
-            items.push(DeveloperInstructions::new(developer_instructions.to_string()).into());
+            developer_sections.push(developer_instructions.to_string());
         }
         // Add developer instructions for memories.
         if let Some(memory_prompt) =
             build_memory_tool_developer_instructions(&turn_context.config.codex_home).await
             && turn_context.features.enabled(Feature::MemoryTool)
         {
-            items.push(DeveloperInstructions::new(memory_prompt).into());
+            developer_sections.push(memory_prompt);
         }
         // Add developer instructions from collaboration_mode if they exist and are non-empty
         let (collaboration_mode, base_instructions) = {
@@ -3024,7 +3050,7 @@ impl Session {
         if let Some(collab_instructions) =
             DeveloperInstructions::from_collaboration_mode(&collaboration_mode)
         {
-            items.push(collab_instructions.into());
+            developer_sections.push(collab_instructions.into_text());
         }
         if self.features.enabled(Feature::Personality)
             && let Some(personality) = turn_context.personality
@@ -3039,34 +3065,53 @@ impl Session {
                         personality,
                     )
             {
-                items.push(
-                    DeveloperInstructions::personality_spec_message(personality_message).into(),
+                developer_sections.push(
+                    DeveloperInstructions::personality_spec_message(personality_message)
+                        .into_text(),
                 );
             }
         }
         if turn_context.features.enabled(Feature::Apps) {
-            items.push(DeveloperInstructions::new(render_apps_section()).into());
+            developer_sections.push(render_apps_section());
         }
         if turn_context.features.enabled(Feature::CodexGitCommit)
             && let Some(commit_message_instruction) = commit_message_trailer_instruction(
                 turn_context.config.commit_attribution.as_deref(),
             )
         {
-            items.push(DeveloperInstructions::new(commit_message_instruction).into());
+            developer_sections.push(commit_message_instruction);
         }
         if let Some(user_instructions) = turn_context.user_instructions.as_deref() {
-            items.push(
+            contextual_user_sections.push(
                 UserInstructions {
                     text: user_instructions.to_string(),
                     directory: turn_context.cwd.to_string_lossy().into_owned(),
                 }
-                .into(),
+                .serialize_to_text(),
             );
         }
-        items.push(ResponseItem::from(EnvironmentContext::from_turn_context(
-            turn_context,
-            shell.as_ref(),
-        )));
+        let subagents = self
+            .services
+            .agent_control
+            .format_environment_context_subagents(self.conversation_id)
+            .await;
+        contextual_user_sections.push(
+            EnvironmentContext::from_turn_context(turn_context, shell.as_ref())
+                .with_subagents(subagents)
+                .serialize_to_xml(),
+        );
+
+        let mut items = Vec::with_capacity(2);
+        if let Some(developer_message) =
+            crate::context_manager::updates::build_developer_update_item(developer_sections)
+        {
+            items.push(developer_message);
+        }
+        if let Some(contextual_user_message) =
+            crate::context_manager::updates::build_contextual_user_message(contextual_user_sections)
+        {
+            items.push(contextual_user_message);
+        }
         items
     }
 
@@ -3111,22 +3156,8 @@ impl Session {
         let reference_context_item = self.reference_context_item().await;
         let should_inject_full_context = reference_context_item.is_none();
         let context_items = if should_inject_full_context {
-            let mut initial_context = self.build_initial_context(turn_context).await;
-            // Full reinjection bypasses the settings-diff path, so add the model-switch
-            // instruction explicitly when needed. Keep it before the rest of full context so
-            // model-specific guidance is read first.
-            if let Some(model_switch_item) =
-                crate::context_manager::updates::build_model_instructions_update_item(
-                    previous_user_turn_model,
-                    turn_context,
-                )
-            {
-                // TODO(ccunningham): When a model switch changes the effective personality
-                // instructions, inject the updated personality spec alongside <model_switch>
-                // here so resume/model-switch paths can avoid forcing full reinjection.
-                initial_context.insert(0, model_switch_item);
-            }
-            initial_context
+            self.build_initial_context(turn_context, previous_user_turn_model)
+                .await
         } else {
             // Steady-state path: append only context diffs to minimize token overhead.
             self.build_settings_update_items(
@@ -3516,9 +3547,9 @@ impl Session {
             use_linux_sandbox_bwrap: turn_context.features.enabled(Feature::UseLinuxSandboxBwrap),
         };
         {
-            let mut cancel_guard = self.services.mcp_startup_cancellation_token.lock().await;
-            cancel_guard.cancel();
-            *cancel_guard = CancellationToken::new();
+            let mut guard = self.services.mcp_startup_cancellation_token.lock().await;
+            guard.cancel();
+            *guard = CancellationToken::new();
         }
         let (refreshed_manager, cancel_token) = McpConnectionManager::new(
             &mcp_servers,
@@ -3532,11 +3563,11 @@ impl Session {
         )
         .await;
         {
-            let mut cancel_guard = self.services.mcp_startup_cancellation_token.lock().await;
-            if cancel_guard.is_cancelled() {
+            let mut guard = self.services.mcp_startup_cancellation_token.lock().await;
+            if guard.is_cancelled() {
                 cancel_token.cancel();
             }
-            *cancel_guard = cancel_token;
+            *guard = cancel_token;
         }
 
         let mut manager = self.services.mcp_connection_manager.write().await;
@@ -4615,7 +4646,9 @@ async fn spawn_review_thread(
     let provider_for_context = provider.clone();
     let otel_manager_for_context = otel_manager.clone();
     let reasoning_effort = per_turn_config.model_reasoning_effort;
-    let reasoning_summary = per_turn_config.model_reasoning_summary;
+    let reasoning_summary = per_turn_config
+        .model_reasoning_summary
+        .unwrap_or(model_info.default_reasoning_summary);
     let session_source = parent_turn_context.session_source.clone();
 
     let per_turn_config = Arc::new(per_turn_config);
@@ -5011,6 +5044,7 @@ pub(crate) async fn run_turn(
                         &sess,
                         &turn_context,
                         InitialContextInjection::BeforeLastUserMessage,
+                        previous_model.as_deref(),
                     )
                     .await
                     .is_err()
@@ -5134,7 +5168,13 @@ async fn run_pre_sampling_compact(
         .unwrap_or(i64::MAX);
     // Compact if the total usage tokens are greater than the auto compact limit
     if total_usage_tokens >= auto_compact_limit {
-        run_auto_compact(sess, turn_context, InitialContextInjection::DoNotInject).await?;
+        run_auto_compact(
+            sess,
+            turn_context,
+            InitialContextInjection::DoNotInject,
+            None,
+        )
+        .await?;
     }
     Ok(())
 }
@@ -5177,6 +5217,7 @@ async fn maybe_run_previous_model_inline_compact(
             sess,
             &previous_model_turn_context,
             InitialContextInjection::DoNotInject,
+            None,
         )
         .await?;
         return Ok(true);
@@ -5188,12 +5229,14 @@ async fn run_auto_compact(
     sess: &Arc<Session>,
     turn_context: &Arc<TurnContext>,
     initial_context_injection: InitialContextInjection,
+    previous_user_turn_model: Option<&str>,
 ) -> CodexResult<()> {
     if should_use_remote_compact_task(&turn_context.provider) {
         run_inline_remote_auto_compact_task(
             Arc::clone(sess),
             Arc::clone(turn_context),
             initial_context_injection,
+            previous_user_turn_model,
         )
         .await?;
     } else {
@@ -5201,6 +5244,7 @@ async fn run_auto_compact(
             Arc::clone(sess),
             Arc::clone(turn_context),
             initial_context_injection,
+            previous_user_turn_model,
         )
         .await?;
     }
@@ -7438,7 +7482,7 @@ mod tests {
         session
             .record_context_updates_and_set_reference_context_item(&turn_context, None)
             .await;
-        expected.extend(session.build_initial_context(&turn_context).await);
+        expected.extend(session.build_initial_context(&turn_context, None).await);
         let history_after_seed = session.clone_history().await;
         assert_eq!(expected, history_after_seed.raw_items());
 
@@ -7600,7 +7644,7 @@ mod tests {
         let reconstruction_turn = session.new_default_turn().await;
         expected.extend(
             session
-                .build_initial_context(reconstruction_turn.as_ref())
+                .build_initial_context(reconstruction_turn.as_ref(), None)
                 .await,
         );
         let history = session.state.lock().await.clone_history();
@@ -7643,7 +7687,7 @@ mod tests {
     async fn thread_rollback_drops_last_turn_from_history() {
         let (sess, tc, rx) = make_session_and_context_with_rx().await;
 
-        let initial_context = sess.build_initial_context(tc.as_ref()).await;
+        let initial_context = sess.build_initial_context(tc.as_ref(), None).await;
         sess.record_into_history(&initial_context, tc.as_ref())
             .await;
 
@@ -7714,7 +7758,7 @@ mod tests {
     async fn thread_rollback_clears_history_when_num_turns_exceeds_existing_turns() {
         let (sess, tc, rx) = make_session_and_context_with_rx().await;
 
-        let initial_context = sess.build_initial_context(tc.as_ref()).await;
+        let initial_context = sess.build_initial_context(tc.as_ref(), None).await;
         sess.record_into_history(&initial_context, tc.as_ref())
             .await;
 
@@ -7742,7 +7786,7 @@ mod tests {
     async fn thread_rollback_fails_when_turn_in_progress() {
         let (sess, tc, rx) = make_session_and_context_with_rx().await;
 
-        let initial_context = sess.build_initial_context(tc.as_ref()).await;
+        let initial_context = sess.build_initial_context(tc.as_ref(), None).await;
         sess.record_into_history(&initial_context, tc.as_ref())
             .await;
 
@@ -7763,7 +7807,7 @@ mod tests {
     async fn thread_rollback_fails_when_num_turns_is_zero() {
         let (sess, tc, rx) = make_session_and_context_with_rx().await;
 
-        let initial_context = sess.build_initial_context(tc.as_ref()).await;
+        let initial_context = sess.build_initial_context(tc.as_ref(), None).await;
         sess.record_into_history(&initial_context, tc.as_ref())
             .await;
 
@@ -8787,7 +8831,7 @@ mod tests {
             .record_context_updates_and_set_reference_context_item(&turn_context, None)
             .await;
         let history = session.clone_history().await;
-        let initial_context = session.build_initial_context(&turn_context).await;
+        let initial_context = session.build_initial_context(&turn_context, None).await;
         assert_eq!(history.raw_items().to_vec(), initial_context);
 
         let current_context = session.reference_context_item().await;
@@ -8831,10 +8875,28 @@ mod tests {
 
         let history = session.clone_history().await;
         let mut expected_history = vec![compacted_summary];
-        expected_history.extend(session.build_initial_context(&turn_context).await);
+        expected_history.extend(session.build_initial_context(&turn_context, None).await);
         assert_eq!(history.raw_items().to_vec(), expected_history);
     }
 
+    #[tokio::test]
+    async fn build_initial_context_prepends_model_switch_message() {
+        let (session, turn_context) = make_session_and_context().await;
+
+        let initial_context = session
+            .build_initial_context(&turn_context, Some("previous-regular-model"))
+            .await;
+
+        let ResponseItem::Message { role, content, .. } = &initial_context[0] else {
+            panic!("expected developer message");
+        };
+        assert_eq!(role, "developer");
+        let [ContentItem::InputText { text }, ..] = content.as_slice() else {
+            panic!("expected developer text");
+        };
+        assert!(text.contains("<model_switch>"));
+    }
+
     #[tokio::test]
     async fn run_user_shell_command_does_not_set_reference_context_item() {
         let (session, _turn_context, rx) = make_session_and_context_with_rx().await;
@@ -9156,7 +9218,7 @@ mod tests {
                     let ContentItem::InputText { text } = content_item else {
                         return false;
                     };
-                    text.contains(crate::session_prefix::TURN_ABORTED_OPEN_TAG)
+                    text.contains(crate::contextual_user_message::TURN_ABORTED_OPEN_TAG)
                 })
             }),
             "expected a model-visible turn aborted marker in history after interrupt"
@@ -9230,7 +9292,7 @@ mod tests {
         // personality_spec) matches reconstruction.
         let reconstruction_turn = session.new_default_turn().await;
         let mut initial_context = session
-            .build_initial_context(reconstruction_turn.as_ref())
+            .build_initial_context(reconstruction_turn.as_ref(), None)
             .await;
         // Ensure personality_spec is present when Personality is enabled, so expected matches
         // what reconstruction produces (build_initial_context may omit it when baked into model).

codex-rs/core/src/compact.rs

@@ -7,7 +7,6 @@ use crate::client_common::ResponseEvent;
 use crate::codex::Session;
 use crate::codex::TurnContext;
 use crate::codex::get_last_assistant_message_from_turn;
-use crate::context_manager::ContextManager;
 use crate::error::CodexErr;
 use crate::error::Result as CodexResult;
 use crate::protocol::CompactedItem;
@@ -51,47 +50,11 @@ pub(crate) fn should_use_remote_compact_task(provider: &ModelProviderInfo) -> bo
     provider.is_openai()
 }
 
-fn is_model_switch_developer_message(item: &ResponseItem) -> bool {
-    match item {
-        ResponseItem::Message { role, content, .. } if role == "developer" => {
-            matches!(
-                content.as_slice(),
-                [ContentItem::InputText { text }] if text.starts_with("<model_switch>\n")
-            )
-        }
-        _ => false,
-    }
-}
-
-pub(crate) fn extract_trailing_model_switch_update_for_compaction_request(
-    history: &mut ContextManager,
-) -> Option<ResponseItem> {
-    let history_items = history.raw_items();
-    let last_user_turn_boundary_index = history_items
-        .iter()
-        .rposition(crate::context_manager::is_user_turn_boundary);
-    let model_switch_index = history_items
-        .iter()
-        .enumerate()
-        .rev()
-        .find_map(|(i, item)| {
-            let is_trailing = last_user_turn_boundary_index.is_none_or(|boundary| i > boundary);
-            if is_trailing && is_model_switch_developer_message(item) {
-                Some(i)
-            } else {
-                None
-            }
-        })?;
-    let mut replacement = history_items.to_vec();
-    let model_switch_item = replacement.remove(model_switch_index);
-    history.replace(replacement);
-    Some(model_switch_item)
-}
-
 pub(crate) async fn run_inline_auto_compact_task(
     sess: Arc<Session>,
     turn_context: Arc<TurnContext>,
     initial_context_injection: InitialContextInjection,
+    previous_user_turn_model: Option<&str>,
 ) -> CodexResult<()> {
     let prompt = turn_context.compact_prompt().to_string();
     let input = vec![UserInput::Text {
@@ -100,7 +63,14 @@ pub(crate) async fn run_inline_auto_compact_task(
         text_elements: Vec::new(),
     }];
 
-    run_compact_task_inner(sess, turn_context, input, initial_context_injection).await?;
+    run_compact_task_inner(
+        sess,
+        turn_context,
+        input,
+        initial_context_injection,
+        previous_user_turn_model,
+    )
+    .await?;
     Ok(())
 }
 
@@ -120,6 +90,7 @@ pub(crate) async fn run_compact_task(
         turn_context,
         input,
         InitialContextInjection::DoNotInject,
+        None,
     )
     .await
 }
@@ -129,6 +100,7 @@ async fn run_compact_task_inner(
     turn_context: Arc<TurnContext>,
     input: Vec<UserInput>,
     initial_context_injection: InitialContextInjection,
+    previous_user_turn_model: Option<&str>,
 ) -> CodexResult<()> {
     let compaction_item = TurnItem::ContextCompaction(ContextCompactionItem::new());
     sess.emit_turn_item_started(&turn_context, &compaction_item)
@@ -136,10 +108,6 @@ async fn run_compact_task_inner(
     let initial_input_for_turn: ResponseInputItem = ResponseInputItem::from(input);
 
     let mut history = sess.clone_history().await;
-    // Keep compaction prompts in-distribution: if a model-switch update was injected at the
-    // tail of history (between turns), exclude it from the compaction request payload.
-    let stripped_model_switch_item =
-        extract_trailing_model_switch_update_for_compaction_request(&mut history);
     history.record_items(
         &[initial_input_for_turn.into()],
         turn_context.truncation_policy,
@@ -240,15 +208,12 @@ async fn run_compact_task_inner(
         initial_context_injection,
         InitialContextInjection::BeforeLastUserMessage
     ) {
-        let initial_context = sess.build_initial_context(turn_context.as_ref()).await;
+        let initial_context = sess
+            .build_initial_context(turn_context.as_ref(), previous_user_turn_model)
+            .await;
         new_history =
             insert_initial_context_before_last_real_user_or_summary(new_history, initial_context);
     }
-    // Reattach the stripped model-switch update only after successful compaction so the model
-    // still sees the switch instructions on the next real sampling request.
-    if let Some(model_switch_item) = stripped_model_switch_item {
-        new_history.push(model_switch_item);
-    }
     let ghost_snapshots: Vec<ResponseItem> = history_items
         .iter()
         .filter(|item| matches!(item, ResponseItem::GhostSnapshot { .. }))
@@ -491,14 +456,18 @@ mod tests {
 
     async fn process_compacted_history_with_test_session(
         compacted_history: Vec<ResponseItem>,
+        previous_user_turn_model: Option<&str>,
     ) -> (Vec<ResponseItem>, Vec<ResponseItem>) {
         let (session, turn_context) = crate::codex::make_session_and_context().await;
-        let initial_context = session.build_initial_context(&turn_context).await;
+        let initial_context = session
+            .build_initial_context(&turn_context, previous_user_turn_model)
+            .await;
         let refreshed = crate::compact_remote::process_compacted_history(
             &session,
             &turn_context,
             compacted_history,
             InitialContextInjection::BeforeLastUserMessage,
+            previous_user_turn_model,
         )
         .await;
         (refreshed, initial_context)
@@ -534,107 +503,6 @@ mod tests {
         assert_eq!(None, joined);
     }
 
-    #[test]
-    fn extract_trailing_model_switch_update_for_compaction_request_removes_trailing_item() {
-        let mut history = ContextManager::new();
-        history.replace(vec![
-            ResponseItem::Message {
-                id: None,
-                role: "user".to_string(),
-                content: vec![ContentItem::InputText {
-                    text: "USER_MESSAGE".to_string(),
-                }],
-                end_turn: None,
-                phase: None,
-            },
-            ResponseItem::Message {
-                id: None,
-                role: "assistant".to_string(),
-                content: vec![ContentItem::OutputText {
-                    text: "ASSISTANT_REPLY".to_string(),
-                }],
-                end_turn: None,
-                phase: None,
-            },
-            ResponseItem::Message {
-                id: None,
-                role: "developer".to_string(),
-                content: vec![ContentItem::InputText {
-                    text: "<model_switch>\nNEW_MODEL_INSTRUCTIONS".to_string(),
-                }],
-                end_turn: None,
-                phase: None,
-            },
-        ]);
-
-        let model_switch_item =
-            extract_trailing_model_switch_update_for_compaction_request(&mut history);
-
-        assert_eq!(history.raw_items().len(), 2);
-        assert!(model_switch_item.is_some());
-        assert!(
-            history
-                .raw_items()
-                .iter()
-                .all(|item| !is_model_switch_developer_message(item))
-        );
-    }
-
-    #[test]
-    fn extract_trailing_model_switch_update_for_compaction_request_keeps_historical_item() {
-        let mut history = ContextManager::new();
-        history.replace(vec![
-            ResponseItem::Message {
-                id: None,
-                role: "user".to_string(),
-                content: vec![ContentItem::InputText {
-                    text: "FIRST_USER_MESSAGE".to_string(),
-                }],
-                end_turn: None,
-                phase: None,
-            },
-            ResponseItem::Message {
-                id: None,
-                role: "developer".to_string(),
-                content: vec![ContentItem::InputText {
-                    text: "<model_switch>\nOLDER_MODEL_INSTRUCTIONS".to_string(),
-                }],
-                end_turn: None,
-                phase: None,
-            },
-            ResponseItem::Message {
-                id: None,
-                role: "assistant".to_string(),
-                content: vec![ContentItem::OutputText {
-                    text: "ASSISTANT_REPLY".to_string(),
-                }],
-                end_turn: None,
-                phase: None,
-            },
-            ResponseItem::Message {
-                id: None,
-                role: "user".to_string(),
-                content: vec![ContentItem::InputText {
-                    text: "SECOND_USER_MESSAGE".to_string(),
-                }],
-                end_turn: None,
-                phase: None,
-            },
-        ]);
-
-        let model_switch_item =
-            extract_trailing_model_switch_update_for_compaction_request(&mut history);
-
-        assert_eq!(history.raw_items().len(), 4);
-        assert!(model_switch_item.is_none());
-        assert!(
-            history
-                .raw_items()
-                .iter()
-                .any(is_model_switch_developer_message)
-        );
-    }
-
     #[test]
     fn collect_user_messages_extracts_user_text_only() {
         let items = vec![
@@ -802,7 +670,7 @@ do things
             },
         ];
         let (refreshed, mut expected) =
-            process_compacted_history_with_test_session(compacted_history).await;
+            process_compacted_history_with_test_session(compacted_history, None).await;
         expected.push(ResponseItem::Message {
             id: None,
             role: "user".to_string(),
@@ -827,7 +695,7 @@ do things
             phase: None,
         }];
         let (refreshed, mut expected) =
-            process_compacted_history_with_test_session(compacted_history).await;
+            process_compacted_history_with_test_session(compacted_history, None).await;
         expected.push(ResponseItem::Message {
             id: None,
             role: "user".to_string(),
@@ -903,7 +771,7 @@ keep me updated
             },
         ];
         let (refreshed, mut expected) =
-            process_compacted_history_with_test_session(compacted_history).await;
+            process_compacted_history_with_test_session(compacted_history, None).await;
         expected.push(ResponseItem::Message {
             id: None,
             role: "user".to_string(),
@@ -949,7 +817,7 @@ keep me updated
         ];
 
         let (refreshed, initial_context) =
-            process_compacted_history_with_test_session(compacted_history).await;
+            process_compacted_history_with_test_session(compacted_history, None).await;
         let mut expected = vec![
             ResponseItem::Message {
                 id: None,
@@ -983,6 +851,46 @@ keep me updated
         assert_eq!(refreshed, expected);
     }
 
+    #[tokio::test]
+    async fn process_compacted_history_reinjects_model_switch_message() {
+        let compacted_history = vec![ResponseItem::Message {
+            id: None,
+            role: "user".to_string(),
+            content: vec![ContentItem::InputText {
+                text: "summary".to_string(),
+            }],
+            end_turn: None,
+            phase: None,
+        }];
+
+        let (refreshed, initial_context) = process_compacted_history_with_test_session(
+            compacted_history,
+            Some("previous-regular-model"),
+        )
+        .await;
+
+        let ResponseItem::Message { role, content, .. } = &initial_context[0] else {
+            panic!("expected developer message");
+        };
+        assert_eq!(role, "developer");
+        let [ContentItem::InputText { text }, ..] = content.as_slice() else {
+            panic!("expected developer text");
+        };
+        assert!(text.contains("<model_switch>"));
+
+        let mut expected = initial_context;
+        expected.push(ResponseItem::Message {
+            id: None,
+            role: "user".to_string(),
+            content: vec![ContentItem::InputText {
+                text: "summary".to_string(),
+            }],
+            end_turn: None,
+            phase: None,
+        });
+        assert_eq!(refreshed, expected);
+    }
+
     #[test]
     fn insert_initial_context_before_last_real_user_or_summary_keeps_summary_last() {
         let compacted_history = vec![

codex-rs/core/src/compact_remote.rs

@@ -4,7 +4,6 @@ use crate::Prompt;
 use crate::codex::Session;
 use crate::codex::TurnContext;
 use crate::compact::InitialContextInjection;
-use crate::compact::extract_trailing_model_switch_update_for_compaction_request;
 use crate::compact::insert_initial_context_before_last_real_user_or_summary;
 use crate::context_manager::ContextManager;
 use crate::context_manager::TotalTokenUsageBreakdown;
@@ -28,8 +27,15 @@ pub(crate) async fn run_inline_remote_auto_compact_task(
     sess: Arc<Session>,
     turn_context: Arc<TurnContext>,
     initial_context_injection: InitialContextInjection,
+    previous_user_turn_model: Option<&str>,
 ) -> CodexResult<()> {
-    run_remote_compact_task_inner(&sess, &turn_context, initial_context_injection).await?;
+    run_remote_compact_task_inner(
+        &sess,
+        &turn_context,
+        initial_context_injection,
+        previous_user_turn_model,
+    )
+    .await?;
     Ok(())
 }
 
@@ -44,16 +50,28 @@ pub(crate) async fn run_remote_compact_task(
     });
     sess.send_event(&turn_context, start_event).await;
 
-    run_remote_compact_task_inner(&sess, &turn_context, InitialContextInjection::DoNotInject).await
+    run_remote_compact_task_inner(
+        &sess,
+        &turn_context,
+        InitialContextInjection::DoNotInject,
+        None,
+    )
+    .await
 }
 
 async fn run_remote_compact_task_inner(
     sess: &Arc<Session>,
     turn_context: &Arc<TurnContext>,
     initial_context_injection: InitialContextInjection,
+    previous_user_turn_model: Option<&str>,
 ) -> CodexResult<()> {
-    if let Err(err) =
-        run_remote_compact_task_inner_impl(sess, turn_context, initial_context_injection).await
+    if let Err(err) = run_remote_compact_task_inner_impl(
+        sess,
+        turn_context,
+        initial_context_injection,
+        previous_user_turn_model,
+    )
+    .await
     {
         let event = EventMsg::Error(
             err.to_error_event(Some("Error running remote compact task".to_string())),
@@ -68,15 +86,12 @@ async fn run_remote_compact_task_inner_impl(
     sess: &Arc<Session>,
     turn_context: &Arc<TurnContext>,
     initial_context_injection: InitialContextInjection,
+    previous_user_turn_model: Option<&str>,
 ) -> CodexResult<()> {
     let compaction_item = TurnItem::ContextCompaction(ContextCompactionItem::new());
     sess.emit_turn_item_started(turn_context, &compaction_item)
         .await;
     let mut history = sess.clone_history().await;
-    // Keep compaction prompts in-distribution: if a model-switch update was injected at the
-    // tail of history (between turns), exclude it from the compaction request payload.
-    let stripped_model_switch_item =
-        extract_trailing_model_switch_update_for_compaction_request(&mut history);
     let base_instructions = sess.get_base_instructions().await;
     let deleted_items = trim_function_call_history_to_fit_context_window(
         &mut history,
@@ -90,7 +105,6 @@ async fn run_remote_compact_task_inner_impl(
             "trimmed history items before remote compaction"
         );
     }
-
     // Required to keep `/undo` available after compaction
     let ghost_snapshots: Vec<ResponseItem> = history
         .raw_items()
@@ -134,13 +148,9 @@ async fn run_remote_compact_task_inner_impl(
         turn_context.as_ref(),
         new_history,
         initial_context_injection,
+        previous_user_turn_model,
     )
     .await;
-    // Reattach the stripped model-switch update only after successful compaction so the model
-    // still sees the switch instructions on the next real sampling request.
-    if let Some(model_switch_item) = stripped_model_switch_item {
-        new_history.push(model_switch_item);
-    }
 
     if !ghost_snapshots.is_empty() {
         new_history.extend(ghost_snapshots);
@@ -170,6 +180,7 @@ pub(crate) async fn process_compacted_history(
     turn_context: &TurnContext,
     mut compacted_history: Vec<ResponseItem>,
     initial_context_injection: InitialContextInjection,
+    previous_user_turn_model: Option<&str>,
 ) -> Vec<ResponseItem> {
     // Mid-turn compaction is the only path that must inject initial context above the last user
     // message in the replacement history. Pre-turn compaction instead injects context after the
@@ -178,7 +189,8 @@ pub(crate) async fn process_compacted_history(
         initial_context_injection,
         InitialContextInjection::BeforeLastUserMessage
     ) {
-        sess.build_initial_context(turn_context).await
+        sess.build_initial_context(turn_context, previous_user_turn_model)
+            .await
     } else {
         Vec::new()
     };
@@ -205,10 +217,12 @@ pub(crate) async fn process_compacted_history(
 fn should_keep_compacted_history_item(item: &ResponseItem) -> bool {
     match item {
         ResponseItem::Message { role, .. } if role == "developer" => false,
-        ResponseItem::Message { role, .. } if role == "user" => matches!(
-            crate::event_mapping::parse_turn_item(item),
-            Some(TurnItem::UserMessage(_))
-        ),
+        ResponseItem::Message { role, .. } if role == "user" => {
+            matches!(
+                crate::event_mapping::parse_turn_item(item),
+                Some(TurnItem::UserMessage(_))
+            )
+        }
         ResponseItem::Message { role, .. } if role == "assistant" => true,
         ResponseItem::Message { .. } => false,
         ResponseItem::Compaction { .. } => true,

codex-rs/core/src/config/mod.rs

@@ -409,9 +409,9 @@ pub struct Config {
     /// global default").
     pub plan_mode_reasoning_effort: Option<ReasoningEffort>,
 
-    /// If not "none", the value to use for `reasoning.summary` when making a
-    /// request using the Responses API.
-    pub model_reasoning_summary: ReasoningSummary,
+    /// Optional value to use for `reasoning.summary` when making a request
+    /// using the Responses API. When unset, the model catalog default is used.
+    pub model_reasoning_summary: Option<ReasoningSummary>,
 
     /// Optional override to force-enable reasoning summaries for the configured model.
     pub model_supports_reasoning_summaries: Option<bool>,
@@ -2138,8 +2138,7 @@ impl Config {
                 .or(cfg.plan_mode_reasoning_effort),
             model_reasoning_summary: config_profile
                 .model_reasoning_summary
-                .or(cfg.model_reasoning_summary)
-                .unwrap_or_default(),
+                .or(cfg.model_reasoning_summary),
             model_supports_reasoning_summaries: cfg.model_supports_reasoning_summaries,
             model_catalog,
             model_verbosity: config_profile.model_verbosity.or(cfg.model_verbosity),
@@ -2464,6 +2463,7 @@ persistence = "none"
         let memories = r#"
 [memories]
 max_raw_memories_for_global = 512
+max_unused_days = 21
 max_rollout_age_days = 42
 max_rollouts_per_startup = 9
 min_rollout_idle_hours = 24
@@ -2475,6 +2475,7 @@ phase_2_model = "gpt-5"
         assert_eq!(
             Some(MemoriesToml {
                 max_raw_memories_for_global: Some(512),
+                max_unused_days: Some(21),
                 max_rollout_age_days: Some(42),
                 max_rollouts_per_startup: Some(9),
                 min_rollout_idle_hours: Some(24),
@@ -2494,6 +2495,7 @@ phase_2_model = "gpt-5"
             config.memories,
             MemoriesConfig {
                 max_raw_memories_for_global: 512,
+                max_unused_days: 21,
                 max_rollout_age_days: 42,
                 max_rollouts_per_startup: 9,
                 min_rollout_idle_hours: 24,
@@ -4758,7 +4760,7 @@ model_verbosity = "high"
                 show_raw_agent_reasoning: false,
                 model_reasoning_effort: Some(ReasoningEffort::High),
                 plan_mode_reasoning_effort: None,
-                model_reasoning_summary: ReasoningSummary::Detailed,
+                model_reasoning_summary: Some(ReasoningSummary::Detailed),
                 model_supports_reasoning_summaries: None,
                 model_catalog: None,
                 model_verbosity: None,
@@ -4884,7 +4886,7 @@ model_verbosity = "high"
             show_raw_agent_reasoning: false,
             model_reasoning_effort: None,
             plan_mode_reasoning_effort: None,
-            model_reasoning_summary: ReasoningSummary::default(),
+            model_reasoning_summary: None,
             model_supports_reasoning_summaries: None,
             model_catalog: None,
             model_verbosity: None,
@@ -5008,7 +5010,7 @@ model_verbosity = "high"
             show_raw_agent_reasoning: false,
             model_reasoning_effort: None,
             plan_mode_reasoning_effort: None,
-            model_reasoning_summary: ReasoningSummary::default(),
+            model_reasoning_summary: None,
             model_supports_reasoning_summaries: None,
             model_catalog: None,
             model_verbosity: None,
@@ -5118,7 +5120,7 @@ model_verbosity = "high"
             show_raw_agent_reasoning: false,
             model_reasoning_effort: Some(ReasoningEffort::High),
             plan_mode_reasoning_effort: None,
-            model_reasoning_summary: ReasoningSummary::Detailed,
+            model_reasoning_summary: Some(ReasoningSummary::Detailed),
             model_supports_reasoning_summaries: None,
             model_catalog: None,
             model_verbosity: Some(Verbosity::High),

codex-rs/core/src/config/types.rs

@@ -27,6 +27,7 @@ pub const DEFAULT_MEMORIES_MAX_ROLLOUTS_PER_STARTUP: usize = 16;
 pub const DEFAULT_MEMORIES_MAX_ROLLOUT_AGE_DAYS: i64 = 30;
 pub const DEFAULT_MEMORIES_MIN_ROLLOUT_IDLE_HOURS: i64 = 6;
 pub const DEFAULT_MEMORIES_MAX_RAW_MEMORIES_FOR_GLOBAL: usize = 1_024;
+pub const DEFAULT_MEMORIES_MAX_UNUSED_DAYS: i64 = 30;
 
 #[derive(Serialize, Deserialize, Debug, Clone, Copy, PartialEq, Eq, JsonSchema)]
 #[serde(rename_all = "kebab-case")]
@@ -363,6 +364,8 @@ pub struct FeedbackConfigToml {
 pub struct MemoriesToml {
     /// Maximum number of recent raw memories retained for global consolidation.
     pub max_raw_memories_for_global: Option<usize>,
+    /// Maximum number of days since a memory was last used before it becomes ineligible for phase 2 selection.
+    pub max_unused_days: Option<i64>,
     /// Maximum age of the threads used for memories.
     pub max_rollout_age_days: Option<i64>,
     /// Maximum number of rollout candidates processed per pass.
@@ -379,6 +382,7 @@ pub struct MemoriesToml {
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct MemoriesConfig {
     pub max_raw_memories_for_global: usize,
+    pub max_unused_days: i64,
     pub max_rollout_age_days: i64,
     pub max_rollouts_per_startup: usize,
     pub min_rollout_idle_hours: i64,
@@ -390,6 +394,7 @@ impl Default for MemoriesConfig {
     fn default() -> Self {
         Self {
             max_raw_memories_for_global: DEFAULT_MEMORIES_MAX_RAW_MEMORIES_FOR_GLOBAL,
+            max_unused_days: DEFAULT_MEMORIES_MAX_UNUSED_DAYS,
             max_rollout_age_days: DEFAULT_MEMORIES_MAX_ROLLOUT_AGE_DAYS,
             max_rollouts_per_startup: DEFAULT_MEMORIES_MAX_ROLLOUTS_PER_STARTUP,
             min_rollout_idle_hours: DEFAULT_MEMORIES_MIN_ROLLOUT_IDLE_HOURS,
@@ -407,6 +412,10 @@ impl From<MemoriesToml> for MemoriesConfig {
                 .max_raw_memories_for_global
                 .unwrap_or(defaults.max_raw_memories_for_global)
                 .min(4096),
+            max_unused_days: toml
+                .max_unused_days
+                .unwrap_or(defaults.max_unused_days)
+                .clamp(0, 365),
             max_rollout_age_days: toml
                 .max_rollout_age_days
                 .unwrap_or(defaults.max_rollout_age_days)

codex-rs/core/src/context_manager/history.rs

@@ -1,14 +1,11 @@
 use crate::codex::TurnContext;
 use crate::context_manager::normalize;
-use crate::instructions::SkillInstructions;
-use crate::instructions::UserInstructions;
-use crate::session_prefix::is_session_prefix;
+use crate::event_mapping::is_contextual_user_message_content;
 use crate::truncate::TruncationPolicy;
 use crate::truncate::approx_token_count;
 use crate::truncate::approx_tokens_from_byte_count_i64;
 use crate::truncate::truncate_function_output_items_with_policy;
 use crate::truncate::truncate_text;
-use crate::user_shell_command::is_user_shell_command_text;
 use codex_protocol::models::BaseInstructions;
 use codex_protocol::models::ContentItem;
 use codex_protocol::models::FunctionCallOutputBody;
@@ -554,33 +551,7 @@ pub(crate) fn is_user_turn_boundary(item: &ResponseItem) -> bool {
         return false;
     };
 
-    if role != "user" {
-        return false;
-    }
-
-    if UserInstructions::is_user_instructions(content)
-        || SkillInstructions::is_skill_instructions(content)
-    {
-        return false;
-    }
-
-    for content_item in content {
-        match content_item {
-            ContentItem::InputText { text } => {
-                if is_session_prefix(text) || is_user_shell_command_text(text) {
-                    return false;
-                }
-            }
-            ContentItem::OutputText { text } => {
-                if is_session_prefix(text) {
-                    return false;
-                }
-            }
-            ContentItem::InputImage { .. } => {}
-        }
-    }
-
-    true
+    role == "user" && !is_contextual_user_message_content(content)
 }
 
 fn user_message_positions(items: &[ResponseItem]) -> Vec<usize> {

codex-rs/core/src/context_manager/history_tests.rs

@@ -563,7 +563,6 @@ fn drop_last_n_user_turns_preserves_prefix() {
 fn drop_last_n_user_turns_ignores_session_prefix_user_messages() {
     let items = vec![
         user_input_text_msg("<environment_context>ctx</environment_context>"),
-        user_input_text_msg("<user_instructions>do the thing</user_instructions>"),
         user_input_text_msg(
             "# AGENTS.md instructions for test_directory\n\n<INSTRUCTIONS>\ntest_text\n</INSTRUCTIONS>",
         ),
@@ -586,7 +585,6 @@ fn drop_last_n_user_turns_ignores_session_prefix_user_messages() {
 
     let expected_prefix_and_first_turn = vec![
         user_input_text_msg("<environment_context>ctx</environment_context>"),
-        user_input_text_msg("<user_instructions>do the thing</user_instructions>"),
         user_input_text_msg(
             "# AGENTS.md instructions for test_directory\n\n<INSTRUCTIONS>\ntest_text\n</INSTRUCTIONS>",
         ),
@@ -608,7 +606,6 @@ fn drop_last_n_user_turns_ignores_session_prefix_user_messages() {
 
     let expected_prefix_only = vec![
         user_input_text_msg("<environment_context>ctx</environment_context>"),
-        user_input_text_msg("<user_instructions>do the thing</user_instructions>"),
         user_input_text_msg(
             "# AGENTS.md instructions for test_directory\n\n<INSTRUCTIONS>\ntest_text\n</INSTRUCTIONS>",
         ),
@@ -623,7 +620,6 @@ fn drop_last_n_user_turns_ignores_session_prefix_user_messages() {
 
     let mut history = create_history_with_items(vec![
         user_input_text_msg("<environment_context>ctx</environment_context>"),
-        user_input_text_msg("<user_instructions>do the thing</user_instructions>"),
         user_input_text_msg(
             "# AGENTS.md instructions for test_directory\n\n<INSTRUCTIONS>\ntest_text\n</INSTRUCTIONS>",
         ),
@@ -644,7 +640,6 @@ fn drop_last_n_user_turns_ignores_session_prefix_user_messages() {
 
     let mut history = create_history_with_items(vec![
         user_input_text_msg("<environment_context>ctx</environment_context>"),
-        user_input_text_msg("<user_instructions>do the thing</user_instructions>"),
         user_input_text_msg(
             "# AGENTS.md instructions for test_directory\n\n<INSTRUCTIONS>\ntest_text\n</INSTRUCTIONS>",
         ),

codex-rs/core/src/context_manager/updates.rs

@@ -4,6 +4,7 @@ use crate::features::Feature;
 use crate::shell::Shell;
 use codex_execpolicy::Policy;
 use codex_protocol::config_types::Personality;
+use codex_protocol::models::ContentItem;
 use codex_protocol::models::DeveloperInstructions;
 use codex_protocol::models::ResponseItem;
 use codex_protocol::openai_models::ModelInfo;
@@ -30,7 +31,7 @@ fn build_permissions_update_item(
     previous: Option<&TurnContextItem>,
     next: &TurnContext,
     exec_policy: &Policy,
-) -> Option<ResponseItem> {
+) -> Option<DeveloperInstructions> {
     let prev = previous?;
     if prev.sandbox_policy == *next.sandbox_policy.get()
         && prev.approval_policy == next.approval_policy.value()
@@ -38,27 +39,26 @@ fn build_permissions_update_item(
         return None;
     }
 
-    Some(
-        DeveloperInstructions::from_policy(
-            next.sandbox_policy.get(),
-            next.approval_policy.value(),
-            exec_policy,
-            &next.cwd,
-            next.features.enabled(Feature::RequestPermissions),
-        )
-        .into(),
-    )
+    Some(DeveloperInstructions::from_policy(
+        next.sandbox_policy.get(),
+        next.approval_policy.value(),
+        exec_policy,
+        &next.cwd,
+        next.features.enabled(Feature::RequestPermissions),
+    ))
 }
 
 fn build_collaboration_mode_update_item(
     previous: Option<&TurnContextItem>,
     next: &TurnContext,
-) -> Option<ResponseItem> {
+) -> Option<DeveloperInstructions> {
     let prev = previous?;
     if prev.collaboration_mode.as_ref() != Some(&next.collaboration_mode) {
         // If the next mode has empty developer instructions, this returns None and we emit no
         // update, so prior collaboration instructions remain in the prompt history.
-        Some(DeveloperInstructions::from_collaboration_mode(&next.collaboration_mode)?.into())
+        Some(DeveloperInstructions::from_collaboration_mode(
+            &next.collaboration_mode,
+        )?)
     } else {
         None
     }
@@ -68,7 +68,7 @@ fn build_personality_update_item(
     previous: Option<&TurnContextItem>,
     next: &TurnContext,
     personality_feature_enabled: bool,
-) -> Option<ResponseItem> {
+) -> Option<DeveloperInstructions> {
     if !personality_feature_enabled {
         return None;
     }
@@ -82,8 +82,7 @@ fn build_personality_update_item(
     {
         let model_info = &next.model_info;
         let personality_message = personality_message_for(model_info, personality);
-        personality_message
-            .map(|message| DeveloperInstructions::personality_spec_message(message).into())
+        personality_message.map(DeveloperInstructions::personality_spec_message)
     } else {
         None
     }
@@ -103,7 +102,7 @@ pub(crate) fn personality_message_for(
 pub(crate) fn build_model_instructions_update_item(
     previous_user_turn_model: Option<&str>,
     next: &TurnContext,
-) -> Option<ResponseItem> {
+) -> Option<DeveloperInstructions> {
     let previous_model = previous_user_turn_model?;
     if previous_model == next.model_info.slug {
         return None;
@@ -114,7 +113,36 @@ pub(crate) fn build_model_instructions_update_item(
         return None;
     }
 
-    Some(DeveloperInstructions::model_switch_message(model_instructions).into())
+    Some(DeveloperInstructions::model_switch_message(
+        model_instructions,
+    ))
+}
+
+pub(crate) fn build_developer_update_item(text_sections: Vec<String>) -> Option<ResponseItem> {
+    build_text_message("developer", text_sections)
+}
+
+pub(crate) fn build_contextual_user_message(text_sections: Vec<String>) -> Option<ResponseItem> {
+    build_text_message("user", text_sections)
+}
+
+fn build_text_message(role: &str, text_sections: Vec<String>) -> Option<ResponseItem> {
+    if text_sections.is_empty() {
+        return None;
+    }
+
+    let content = text_sections
+        .into_iter()
+        .map(|text| ContentItem::InputText { text })
+        .collect();
+
+    Some(ResponseItem::Message {
+        id: None,
+        role: role.to_string(),
+        content,
+        end_turn: None,
+        phase: None,
+    })
 }
 
 pub(crate) fn build_settings_update_items(
@@ -125,29 +153,26 @@ pub(crate) fn build_settings_update_items(
     exec_policy: &Policy,
     personality_feature_enabled: bool,
 ) -> Vec<ResponseItem> {
-    let mut update_items = Vec::new();
+    let contextual_user_message = build_environment_update_item(previous, next, shell);
+    let developer_update_sections = [
+        // Keep model-switch instructions first so model-specific guidance is read before
+        // any other context diffs on this turn.
+        build_model_instructions_update_item(previous_user_turn_model, next),
+        build_permissions_update_item(previous, next, exec_policy),
+        build_collaboration_mode_update_item(previous, next),
+        build_personality_update_item(previous, next, personality_feature_enabled),
+    ]
+    .into_iter()
+    .flatten()
+    .map(DeveloperInstructions::into_text)
+    .collect();
 
-    // Keep model-switch instructions first so model-specific guidance is read before
-    // any other context diffs on this turn.
-    if let Some(model_instructions_item) =
-        build_model_instructions_update_item(previous_user_turn_model, next)
-    {
-        update_items.push(model_instructions_item);
+    let mut items = Vec::with_capacity(2);
+    if let Some(developer_message) = build_developer_update_item(developer_update_sections) {
+        items.push(developer_message);
     }
-    if let Some(env_item) = build_environment_update_item(previous, next, shell) {
-        update_items.push(env_item);
+    if let Some(contextual_user_message) = contextual_user_message {
+        items.push(contextual_user_message);
     }
-    if let Some(permissions_item) = build_permissions_update_item(previous, next, exec_policy) {
-        update_items.push(permissions_item);
-    }
-    if let Some(collaboration_mode_item) = build_collaboration_mode_update_item(previous, next) {
-        update_items.push(collaboration_mode_item);
-    }
-    if let Some(personality_item) =
-        build_personality_update_item(previous, next, personality_feature_enabled)
-    {
-        update_items.push(personality_item);
-    }
-
-    update_items
+    items
 }

codex-rs/core/src/contextual_user_message.rs

@@ -0,0 +1,139 @@
+use codex_protocol::models::ContentItem;
+use codex_protocol::models::ResponseItem;
+use codex_protocol::protocol::ENVIRONMENT_CONTEXT_CLOSE_TAG;
+use codex_protocol::protocol::ENVIRONMENT_CONTEXT_OPEN_TAG;
+
+pub(crate) const AGENTS_MD_START_MARKER: &str = "# AGENTS.md instructions for ";
+pub(crate) const AGENTS_MD_END_MARKER: &str = "</INSTRUCTIONS>";
+pub(crate) const SKILL_OPEN_TAG: &str = "<skill>";
+pub(crate) const SKILL_CLOSE_TAG: &str = "</skill>";
+pub(crate) const USER_SHELL_COMMAND_OPEN_TAG: &str = "<user_shell_command>";
+pub(crate) const USER_SHELL_COMMAND_CLOSE_TAG: &str = "</user_shell_command>";
+pub(crate) const TURN_ABORTED_OPEN_TAG: &str = "<turn_aborted>";
+pub(crate) const TURN_ABORTED_CLOSE_TAG: &str = "</turn_aborted>";
+pub(crate) const SUBAGENT_NOTIFICATION_OPEN_TAG: &str = "<subagent_notification>";
+pub(crate) const SUBAGENT_NOTIFICATION_CLOSE_TAG: &str = "</subagent_notification>";
+
+#[derive(Clone, Copy)]
+pub(crate) struct ContextualUserFragmentDefinition {
+    start_marker: &'static str,
+    end_marker: &'static str,
+}
+
+impl ContextualUserFragmentDefinition {
+    pub(crate) const fn new(start_marker: &'static str, end_marker: &'static str) -> Self {
+        Self {
+            start_marker,
+            end_marker,
+        }
+    }
+
+    pub(crate) fn matches_text(&self, text: &str) -> bool {
+        let trimmed = text.trim_start();
+        let starts_with_marker = trimmed
+            .get(..self.start_marker.len())
+            .is_some_and(|candidate| candidate.eq_ignore_ascii_case(self.start_marker));
+        let trimmed = trimmed.trim_end();
+        let ends_with_marker = trimmed
+            .get(trimmed.len().saturating_sub(self.end_marker.len())..)
+            .is_some_and(|candidate| candidate.eq_ignore_ascii_case(self.end_marker));
+        starts_with_marker && ends_with_marker
+    }
+
+    pub(crate) const fn start_marker(&self) -> &'static str {
+        self.start_marker
+    }
+
+    pub(crate) const fn end_marker(&self) -> &'static str {
+        self.end_marker
+    }
+
+    pub(crate) fn wrap(&self, body: String) -> String {
+        format!("{}\n{}\n{}", self.start_marker, body, self.end_marker)
+    }
+
+    pub(crate) fn into_message(self, text: String) -> ResponseItem {
+        ResponseItem::Message {
+            id: None,
+            role: "user".to_string(),
+            content: vec![ContentItem::InputText { text }],
+            end_turn: None,
+            phase: None,
+        }
+    }
+}
+
+pub(crate) const AGENTS_MD_FRAGMENT: ContextualUserFragmentDefinition =
+    ContextualUserFragmentDefinition::new(AGENTS_MD_START_MARKER, AGENTS_MD_END_MARKER);
+pub(crate) const ENVIRONMENT_CONTEXT_FRAGMENT: ContextualUserFragmentDefinition =
+    ContextualUserFragmentDefinition::new(
+        ENVIRONMENT_CONTEXT_OPEN_TAG,
+        ENVIRONMENT_CONTEXT_CLOSE_TAG,
+    );
+pub(crate) const SKILL_FRAGMENT: ContextualUserFragmentDefinition =
+    ContextualUserFragmentDefinition::new(SKILL_OPEN_TAG, SKILL_CLOSE_TAG);
+pub(crate) const USER_SHELL_COMMAND_FRAGMENT: ContextualUserFragmentDefinition =
+    ContextualUserFragmentDefinition::new(
+        USER_SHELL_COMMAND_OPEN_TAG,
+        USER_SHELL_COMMAND_CLOSE_TAG,
+    );
+pub(crate) const TURN_ABORTED_FRAGMENT: ContextualUserFragmentDefinition =
+    ContextualUserFragmentDefinition::new(TURN_ABORTED_OPEN_TAG, TURN_ABORTED_CLOSE_TAG);
+pub(crate) const SUBAGENT_NOTIFICATION_FRAGMENT: ContextualUserFragmentDefinition =
+    ContextualUserFragmentDefinition::new(
+        SUBAGENT_NOTIFICATION_OPEN_TAG,
+        SUBAGENT_NOTIFICATION_CLOSE_TAG,
+    );
+
+const CONTEXTUAL_USER_FRAGMENTS: &[ContextualUserFragmentDefinition] = &[
+    AGENTS_MD_FRAGMENT,
+    ENVIRONMENT_CONTEXT_FRAGMENT,
+    SKILL_FRAGMENT,
+    USER_SHELL_COMMAND_FRAGMENT,
+    TURN_ABORTED_FRAGMENT,
+    SUBAGENT_NOTIFICATION_FRAGMENT,
+];
+
+pub(crate) fn is_contextual_user_fragment(content_item: &ContentItem) -> bool {
+    let ContentItem::InputText { text } = content_item else {
+        return false;
+    };
+    CONTEXTUAL_USER_FRAGMENTS
+        .iter()
+        .any(|definition| definition.matches_text(text))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn detects_environment_context_fragment() {
+        assert!(is_contextual_user_fragment(&ContentItem::InputText {
+            text: "<environment_context>\n<cwd>/tmp</cwd>\n</environment_context>".to_string(),
+        }));
+    }
+
+    #[test]
+    fn detects_agents_instructions_fragment() {
+        assert!(is_contextual_user_fragment(&ContentItem::InputText {
+            text: "# AGENTS.md instructions for /tmp\n\n<INSTRUCTIONS>\nbody\n</INSTRUCTIONS>"
+                .to_string(),
+        }));
+    }
+
+    #[test]
+    fn detects_subagent_notification_fragment_case_insensitively() {
+        assert!(
+            SUBAGENT_NOTIFICATION_FRAGMENT
+                .matches_text("<SUBAGENT_NOTIFICATION>{}</subagent_notification>")
+        );
+    }
+
+    #[test]
+    fn ignores_regular_user_text() {
+        assert!(!is_contextual_user_fragment(&ContentItem::InputText {
+            text: "hello".to_string(),
+        }));
+    }
+}

codex-rs/core/src/environment_context.rs

@@ -1,9 +1,7 @@
 use crate::codex::TurnContext;
+use crate::contextual_user_message::ENVIRONMENT_CONTEXT_FRAGMENT;
 use crate::shell::Shell;
-use codex_protocol::models::ContentItem;
 use codex_protocol::models::ResponseItem;
-use codex_protocol::protocol::ENVIRONMENT_CONTEXT_CLOSE_TAG;
-use codex_protocol::protocol::ENVIRONMENT_CONTEXT_OPEN_TAG;
 use codex_protocol::protocol::TurnContextItem;
 use codex_protocol::protocol::TurnContextNetworkItem;
 use serde::Deserialize;
@@ -16,6 +14,7 @@ pub(crate) struct EnvironmentContext {
     pub cwd: Option<PathBuf>,
     pub shell: Shell,
     pub network: Option<NetworkContext>,
+    pub subagents: Option<String>,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Default)]
@@ -25,11 +24,17 @@ pub(crate) struct NetworkContext {
 }
 
 impl EnvironmentContext {
-    pub fn new(cwd: Option<PathBuf>, shell: Shell, network: Option<NetworkContext>) -> Self {
+    pub fn new(
+        cwd: Option<PathBuf>,
+        shell: Shell,
+        network: Option<NetworkContext>,
+        subagents: Option<String>,
+    ) -> Self {
         Self {
             cwd,
             shell,
             network,
+            subagents,
         }
     }
 
@@ -40,10 +45,10 @@ impl EnvironmentContext {
         let EnvironmentContext {
             cwd,
             network,
-            // should compare all fields except shell
+            subagents,
             shell: _,
         } = other;
-        self.cwd == *cwd && self.network == *network
+        self.cwd == *cwd && self.network == *network && self.subagents == *subagents
     }
 
     pub fn diff_from_turn_context_item(
@@ -63,7 +68,7 @@ impl EnvironmentContext {
         } else {
             before_network
         };
-        EnvironmentContext::new(cwd, shell.clone(), network)
+        EnvironmentContext::new(cwd, shell.clone(), network, None)
     }
 
     pub fn from_turn_context(turn_context: &TurnContext, shell: &Shell) -> Self {
@@ -71,6 +76,7 @@ impl EnvironmentContext {
             Some(turn_context.cwd.clone()),
             shell.clone(),
             Self::network_from_turn_context(turn_context),
+            None,
         )
     }
 
@@ -79,9 +85,17 @@ impl EnvironmentContext {
             Some(turn_context_item.cwd.clone()),
             shell.clone(),
             Self::network_from_turn_context_item(turn_context_item),
+            None,
         )
     }
 
+    pub fn with_subagents(mut self, subagents: String) -> Self {
+        if !subagents.is_empty() {
+            self.subagents = Some(subagents);
+        }
+        self
+    }
+
     fn network_from_turn_context(turn_context: &TurnContext) -> Option<NetworkContext> {
         let network = turn_context
             .config
@@ -122,7 +136,7 @@ impl EnvironmentContext {
     /// </environment_context>
     /// ```
     pub fn serialize_to_xml(self) -> String {
-        let mut lines = vec![ENVIRONMENT_CONTEXT_OPEN_TAG.to_string()];
+        let mut lines = Vec::new();
         if let Some(cwd) = self.cwd {
             lines.push(format!("  <cwd>{}</cwd>", cwd.to_string_lossy()));
         }
@@ -145,22 +159,18 @@ impl EnvironmentContext {
                 // lines.push("  <network enabled=\"false\" />".to_string());
             }
         }
-        lines.push(ENVIRONMENT_CONTEXT_CLOSE_TAG.to_string());
-        lines.join("\n")
+        if let Some(subagents) = self.subagents {
+            lines.push("  <subagents>".to_string());
+            lines.extend(subagents.lines().map(|line| format!("    {line}")));
+            lines.push("  </subagents>".to_string());
+        }
+        ENVIRONMENT_CONTEXT_FRAGMENT.wrap(lines.join("\n"))
     }
 }
 
 impl From<EnvironmentContext> for ResponseItem {
     fn from(ec: EnvironmentContext) -> Self {
-        ResponseItem::Message {
-            id: None,
-            role: "user".to_string(),
-            content: vec![ContentItem::InputText {
-                text: ec.serialize_to_xml(),
-            }],
-            end_turn: None,
-            phase: None,
-        }
+        ENVIRONMENT_CONTEXT_FRAGMENT.into_message(ec.serialize_to_xml())
     }
 }
 
@@ -183,7 +193,7 @@ mod tests {
     #[test]
     fn serialize_workspace_write_environment_context() {
         let cwd = test_path_buf("/repo");
-        let context = EnvironmentContext::new(Some(cwd.clone()), fake_shell(), None);
+        let context = EnvironmentContext::new(Some(cwd.clone()), fake_shell(), None, None);
 
         let expected = format!(
             r#"<environment_context>
@@ -202,8 +212,12 @@ mod tests {
             allowed_domains: vec!["api.example.com".to_string(), "*.openai.com".to_string()],
             denied_domains: vec!["blocked.example.com".to_string()],
         };
-        let context =
-            EnvironmentContext::new(Some(test_path_buf("/repo")), fake_shell(), Some(network));
+        let context = EnvironmentContext::new(
+            Some(test_path_buf("/repo")),
+            fake_shell(),
+            Some(network),
+            None,
+        );
 
         let expected = format!(
             r#"<environment_context>
@@ -223,7 +237,7 @@ mod tests {
 
     #[test]
     fn serialize_read_only_environment_context() {
-        let context = EnvironmentContext::new(None, fake_shell(), None);
+        let context = EnvironmentContext::new(None, fake_shell(), None, None);
 
         let expected = r#"<environment_context>
   <shell>bash</shell>
@@ -234,7 +248,7 @@ mod tests {
 
     #[test]
     fn serialize_external_sandbox_environment_context() {
-        let context = EnvironmentContext::new(None, fake_shell(), None);
+        let context = EnvironmentContext::new(None, fake_shell(), None, None);
 
         let expected = r#"<environment_context>
   <shell>bash</shell>
@@ -245,7 +259,7 @@ mod tests {
 
     #[test]
     fn serialize_external_sandbox_with_restricted_network_environment_context() {
-        let context = EnvironmentContext::new(None, fake_shell(), None);
+        let context = EnvironmentContext::new(None, fake_shell(), None, None);
 
         let expected = r#"<environment_context>
   <shell>bash</shell>
@@ -256,7 +270,7 @@ mod tests {
 
     #[test]
     fn serialize_full_access_environment_context() {
-        let context = EnvironmentContext::new(None, fake_shell(), None);
+        let context = EnvironmentContext::new(None, fake_shell(), None, None);
 
         let expected = r#"<environment_context>
   <shell>bash</shell>
@@ -267,23 +281,29 @@ mod tests {
 
     #[test]
     fn equals_except_shell_compares_cwd() {
-        let context1 = EnvironmentContext::new(Some(PathBuf::from("/repo")), fake_shell(), None);
-        let context2 = EnvironmentContext::new(Some(PathBuf::from("/repo")), fake_shell(), None);
+        let context1 =
+            EnvironmentContext::new(Some(PathBuf::from("/repo")), fake_shell(), None, None);
+        let context2 =
+            EnvironmentContext::new(Some(PathBuf::from("/repo")), fake_shell(), None, None);
         assert!(context1.equals_except_shell(&context2));
     }
 
     #[test]
     fn equals_except_shell_ignores_sandbox_policy() {
-        let context1 = EnvironmentContext::new(Some(PathBuf::from("/repo")), fake_shell(), None);
-        let context2 = EnvironmentContext::new(Some(PathBuf::from("/repo")), fake_shell(), None);
+        let context1 =
+            EnvironmentContext::new(Some(PathBuf::from("/repo")), fake_shell(), None, None);
+        let context2 =
+            EnvironmentContext::new(Some(PathBuf::from("/repo")), fake_shell(), None, None);
 
         assert!(context1.equals_except_shell(&context2));
     }
 
     #[test]
     fn equals_except_shell_compares_cwd_differences() {
-        let context1 = EnvironmentContext::new(Some(PathBuf::from("/repo1")), fake_shell(), None);
-        let context2 = EnvironmentContext::new(Some(PathBuf::from("/repo2")), fake_shell(), None);
+        let context1 =
+            EnvironmentContext::new(Some(PathBuf::from("/repo1")), fake_shell(), None, None);
+        let context2 =
+            EnvironmentContext::new(Some(PathBuf::from("/repo2")), fake_shell(), None, None);
 
         assert!(!context1.equals_except_shell(&context2));
     }
@@ -298,6 +318,7 @@ mod tests {
                 shell_snapshot: crate::shell::empty_shell_snapshot_receiver(),
             },
             None,
+            None,
         );
         let context2 = EnvironmentContext::new(
             Some(PathBuf::from("/repo")),
@@ -307,8 +328,33 @@ mod tests {
                 shell_snapshot: crate::shell::empty_shell_snapshot_receiver(),
             },
             None,
+            None,
         );
 
         assert!(context1.equals_except_shell(&context2));
     }
+
+    #[test]
+    fn serialize_environment_context_with_subagents() {
+        let context = EnvironmentContext::new(
+            Some(test_path_buf("/repo")),
+            fake_shell(),
+            None,
+            Some("- agent-1: atlas\n- agent-2".to_string()),
+        );
+
+        let expected = format!(
+            r#"<environment_context>
+  <cwd>{}</cwd>
+  <shell>bash</shell>
+  <subagents>
+    - agent-1: atlas
+    - agent-2
+  </subagents>
+</environment_context>"#,
+            test_path_buf("/repo").display()
+        );
+
+        assert_eq!(context.serialize_to_xml(), expected);
+    }
 }

codex-rs/core/src/event_mapping.rs

@@ -18,16 +18,15 @@ use codex_protocol::user_input::UserInput;
 use tracing::warn;
 use uuid::Uuid;
 
-use crate::instructions::SkillInstructions;
-use crate::instructions::UserInstructions;
-use crate::session_prefix::is_session_prefix;
-use crate::user_shell_command::is_user_shell_command_text;
+use crate::contextual_user_message::is_contextual_user_fragment;
 use crate::web_search::web_search_action_detail;
 
+pub(crate) fn is_contextual_user_message_content(message: &[ContentItem]) -> bool {
+    message.iter().any(is_contextual_user_fragment)
+}
+
 fn parse_user_message(message: &[ContentItem]) -> Option<UserMessageItem> {
-    if UserInstructions::is_user_instructions(message)
-        || SkillInstructions::is_skill_instructions(message)
-    {
+    if is_contextual_user_message_content(message) {
         return None;
     }
 
@@ -44,9 +43,6 @@ fn parse_user_message(message: &[ContentItem]) -> Option<UserMessageItem> {
                 {
                     continue;
                 }
-                if is_session_prefix(text) || is_user_shell_command_text(text) {
-                    return None;
-                }
                 content.push(UserInput::Text {
                     text: text.clone(),
                     // Model input content does not carry UI element ranges.
@@ -59,9 +55,6 @@ fn parse_user_message(message: &[ContentItem]) -> Option<UserMessageItem> {
                 });
             }
             ContentItem::OutputText { text } => {
-                if is_session_prefix(text) {
-                    return None;
-                }
                 warn!("Output text in user message: {}", text);
             }
         }
@@ -299,7 +292,7 @@ mod tests {
                 id: None,
                 role: "user".to_string(),
                 content: vec![ContentItem::InputText {
-                    text: "<user_instructions>test_text</user_instructions>".to_string(),
+                    text: "# AGENTS.md instructions for test_directory\n\n<INSTRUCTIONS>\ntest_text\n</INSTRUCTIONS>".to_string(),
                 }],
                 end_turn: None,
             phase: None,
@@ -341,6 +334,22 @@ mod tests {
                 end_turn: None,
             phase: None,
             },
+            ResponseItem::Message {
+                id: None,
+                role: "user".to_string(),
+                content: vec![
+                    ContentItem::InputText {
+                        text: "<environment_context>ctx</environment_context>".to_string(),
+                    },
+                    ContentItem::InputText {
+                        text:
+                            "# AGENTS.md instructions for dir\n\n<INSTRUCTIONS>\nbody\n</INSTRUCTIONS>"
+                                .to_string(),
+                    },
+                ],
+                end_turn: None,
+                phase: None,
+            },
         ];
 
         for item in items {

codex-rs/core/src/features.rs

@@ -463,7 +463,7 @@ pub const FEATURES: &[FeatureSpec] = &[
         key: "js_repl",
         stage: Stage::Experimental {
             name: "JavaScript REPL",
-            menu_description: "Enable a persistent Node-backed JavaScript REPL for interactive website debugging and other inline JavaScript execution capabilities. Requires Node >= v24.13.1 installed.",
+            menu_description: "Enable a persistent Node-backed JavaScript REPL for interactive website debugging and other inline JavaScript execution capabilities. Requires Node >= v22.22.0 installed.",
             announcement: "NEW: JavaScript REPL is now available in /experimental. Enable it, then start a new chat or restart Codex to use it.",
         },
         default_enabled: false,

codex-rs/core/src/instructions/mod.rs

@@ -1,6 +1,5 @@
 mod user_instructions;
 
 pub(crate) use user_instructions::SkillInstructions;
-pub use user_instructions::USER_INSTRUCTIONS_OPEN_TAG_LEGACY;
 pub use user_instructions::USER_INSTRUCTIONS_PREFIX;
 pub(crate) use user_instructions::UserInstructions;

codex-rs/core/src/instructions/user_instructions.rs

@@ -1,12 +1,12 @@
 use serde::Deserialize;
 use serde::Serialize;
 
-use codex_protocol::models::ContentItem;
 use codex_protocol::models::ResponseItem;
 
-pub const USER_INSTRUCTIONS_OPEN_TAG_LEGACY: &str = "<user_instructions>";
+use crate::contextual_user_message::AGENTS_MD_FRAGMENT;
+use crate::contextual_user_message::SKILL_FRAGMENT;
+
 pub const USER_INSTRUCTIONS_PREFIX: &str = "# AGENTS.md instructions for ";
-pub const SKILL_INSTRUCTIONS_PREFIX: &str = "<skill";
 
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
 #[serde(rename = "user_instructions", rename_all = "snake_case")]
@@ -16,31 +16,20 @@ pub(crate) struct UserInstructions {
 }
 
 impl UserInstructions {
-    pub fn is_user_instructions(message: &[ContentItem]) -> bool {
-        if let [ContentItem::InputText { text }] = message {
-            text.starts_with(USER_INSTRUCTIONS_PREFIX)
-                || text.starts_with(USER_INSTRUCTIONS_OPEN_TAG_LEGACY)
-        } else {
-            false
-        }
+    pub(crate) fn serialize_to_text(&self) -> String {
+        format!(
+            "{prefix}{directory}\n\n<INSTRUCTIONS>\n{contents}\n{suffix}",
+            prefix = AGENTS_MD_FRAGMENT.start_marker(),
+            directory = self.directory,
+            contents = self.text,
+            suffix = AGENTS_MD_FRAGMENT.end_marker(),
+        )
     }
 }
 
 impl From<UserInstructions> for ResponseItem {
     fn from(ui: UserInstructions) -> Self {
-        ResponseItem::Message {
-            id: None,
-            role: "user".to_string(),
-            content: vec![ContentItem::InputText {
-                text: format!(
-                    "{USER_INSTRUCTIONS_PREFIX}{directory}\n\n<INSTRUCTIONS>\n{contents}\n</INSTRUCTIONS>",
-                    directory = ui.directory,
-                    contents = ui.text
-                ),
-            }],
-            end_turn: None,
-            phase: None,
-        }
+        AGENTS_MD_FRAGMENT.into_message(ui.serialize_to_text())
     }
 }
 
@@ -52,36 +41,21 @@ pub(crate) struct SkillInstructions {
     pub contents: String,
 }
 
-impl SkillInstructions {
-    pub fn is_skill_instructions(message: &[ContentItem]) -> bool {
-        if let [ContentItem::InputText { text }] = message {
-            text.starts_with(SKILL_INSTRUCTIONS_PREFIX)
-        } else {
-            false
-        }
-    }
-}
+impl SkillInstructions {}
 
 impl From<SkillInstructions> for ResponseItem {
     fn from(si: SkillInstructions) -> Self {
-        ResponseItem::Message {
-            id: None,
-            role: "user".to_string(),
-            content: vec![ContentItem::InputText {
-                text: format!(
-                    "<skill>\n<name>{}</name>\n<path>{}</path>\n{}\n</skill>",
-                    si.name, si.path, si.contents
-                ),
-            }],
-            end_turn: None,
-            phase: None,
-        }
+        SKILL_FRAGMENT.into_message(SKILL_FRAGMENT.wrap(format!(
+            "<name>{}</name>\n<path>{}</path>\n{}",
+            si.name, si.path, si.contents
+        )))
     }
 }
 
 #[cfg(test)]
 mod tests {
     use super::*;
+    use codex_protocol::models::ContentItem;
     use pretty_assertions::assert_eq;
 
     #[test]
@@ -110,21 +84,10 @@ mod tests {
 
     #[test]
     fn test_is_user_instructions() {
-        assert!(UserInstructions::is_user_instructions(
-            &[ContentItem::InputText {
-                text: "# AGENTS.md instructions for test_directory\n\n<INSTRUCTIONS>\ntest_text\n</INSTRUCTIONS>".to_string(),
-            }]
+        assert!(AGENTS_MD_FRAGMENT.matches_text(
+            "# AGENTS.md instructions for test_directory\n\n<INSTRUCTIONS>\ntest_text\n</INSTRUCTIONS>"
         ));
-        assert!(UserInstructions::is_user_instructions(&[
-            ContentItem::InputText {
-                text: "<user_instructions>test_text</user_instructions>".to_string(),
-            }
-        ]));
-        assert!(!UserInstructions::is_user_instructions(&[
-            ContentItem::InputText {
-                text: "test_text".to_string(),
-            }
-        ]));
+        assert!(!AGENTS_MD_FRAGMENT.matches_text("test_text"));
     }
 
     #[test]
@@ -154,16 +117,9 @@ mod tests {
 
     #[test]
     fn test_is_skill_instructions() {
-        assert!(SkillInstructions::is_skill_instructions(&[
-            ContentItem::InputText {
-                text: "<skill>\n<name>demo-skill</name>\n<path>skills/demo/SKILL.md</path>\nbody\n</skill>"
-                    .to_string(),
-            }
-        ]));
-        assert!(!SkillInstructions::is_skill_instructions(&[
-            ContentItem::InputText {
-                text: "regular text".to_string(),
-            }
-        ]));
+        assert!(SKILL_FRAGMENT.matches_text(
+            "<skill>\n<name>demo-skill</name>\n<path>skills/demo/SKILL.md</path>\nbody\n</skill>"
+        ));
+        assert!(!SKILL_FRAGMENT.matches_text("regular text"));
     }
 }

codex-rs/core/src/lib.rs

@@ -27,6 +27,7 @@ pub mod config;
 pub mod config_loader;
 pub mod connectors;
 mod context_manager;
+mod contextual_user_message;
 pub mod custom_prompts;
 pub mod env;
 mod environment_context;

codex-rs/core/src/memories/README.md

@@ -59,7 +59,14 @@ Phase 2 consolidates the latest stage-1 outputs into the filesystem memory artif
 What it does:
 
 - claims a single global phase-2 job (so only one consolidation runs at a time)
-- loads a bounded set of the most recent stage-1 outputs from the state DB (the per-rollout memories produced by Phase 1, used as the consolidation input set)
+- loads a bounded set of stage-1 outputs from the state DB using phase-2
+  selection rules:
+  - ignores memories whose `last_usage` falls outside the configured
+    `max_unused_days` window
+  - for memories with no `last_usage`, falls back to `generated_at` so fresh
+    never-used memories can still be selected
+  - ranks eligible memories by `usage_count` first, then by the most recent
+    `last_usage` / `generated_at`
 - computes a completion watermark from the claimed watermark + newest input timestamps
 - syncs local memory artifacts under the memories root:
   - `raw_memories.md` (merged raw memories, latest first)
@@ -70,11 +77,31 @@ What it does:
 If there is input, it then:
 
 - spawns an internal consolidation sub-agent
+- builds the Phase 2 prompt with a diff of the current Phase 1 input
+  selection versus the last successful Phase 2 selection (`added`,
+  `retained`, `removed`)
 - runs it with no approvals, no network, and local write access only
 - disables collab for that agent (to prevent recursive delegation)
 - watches the agent status and heartbeats the global job lease while it runs
 - marks the phase-2 job success/failure in the state DB when the agent finishes
 
+Selection diff behavior:
+
+- successful Phase 2 runs mark the exact stage-1 snapshots they consumed with
+  `selected_for_phase2 = 1` and persist the matching
+  `selected_for_phase2_source_updated_at`
+- Phase 1 upserts preserve the previous `selected_for_phase2` baseline until
+  the next successful Phase 2 run rewrites it
+- the next Phase 2 run compares the current top-N stage-1 inputs against that
+  prior snapshot selection to label inputs as `added` or `retained`; a
+  refreshed thread stays `added` until Phase 2 successfully selects its newer
+  snapshot
+- rows that were previously selected but still exist outside the current top-N
+  selection are surfaced as `removed`
+- before the agent starts, local `rollout_summaries/` and `raw_memories.md`
+  keep the union of the current selection and the previous successful
+  selection, so removed-thread evidence stays available during forgetting
+
 Watermark behavior:
 
 - The global phase-2 job claim includes an input watermark representing the latest input timestamp known when the job was claimed.

codex-rs/core/src/memories/phase2.rs

@@ -8,6 +8,7 @@ use crate::memories::metrics;
 use crate::memories::phase_two;
 use crate::memories::prompts::build_consolidation_prompt;
 use crate::memories::storage::rebuild_raw_memories_file_from_memories;
+use crate::memories::storage::rollout_summary_file_stem;
 use crate::memories::storage::sync_rollout_summaries_from_memories;
 use codex_config::Constrained;
 use codex_protocol::ThreadId;
@@ -17,8 +18,10 @@ use codex_protocol::protocol::SessionSource;
 use codex_protocol::protocol::SubAgentSource;
 use codex_protocol::protocol::TokenUsage;
 use codex_protocol::user_input::UserInput;
+use codex_state::Stage1Output;
 use codex_state::StateRuntime;
 use codex_utils_absolute_path::AbsolutePathBuf;
+use std::collections::HashSet;
 use std::sync::Arc;
 use std::time::Duration;
 use tokio::sync::watch;
@@ -50,6 +53,7 @@ pub(super) async fn run(session: &Arc<Session>, config: Arc<Config>) {
     };
     let root = memory_root(&config.codex_home);
     let max_raw_memories = config.memories.max_raw_memories_for_global;
+    let max_unused_days = config.memories.max_unused_days;
 
     // 1. Claim the job.
     let claim = match job::claim(session, db).await {
@@ -73,21 +77,27 @@ pub(super) async fn run(session: &Arc<Session>, config: Arc<Config>) {
     };
 
     // 3. Query the memories
-    let raw_memories = match db.list_stage1_outputs_for_global(max_raw_memories).await {
-        Ok(memories) => memories,
+    let selection = match db
+        .get_phase2_input_selection(max_raw_memories, max_unused_days)
+        .await
+    {
+        Ok(selection) => selection,
         Err(err) => {
             tracing::error!("failed to list stage1 outputs from global: {}", err);
             job::failed(session, db, &claim, "failed_load_stage1_outputs").await;
             return;
         }
     };
+    let raw_memories = selection.selected.to_vec();
+    let artifact_memories = artifact_memories_for_phase2(&selection);
     let new_watermark = get_watermark(claim.watermark, &raw_memories);
 
     // 4. Update the file system by syncing the raw memories with the one extracted from DB at
     //    step 3
     // [`rollout_summaries/`]
     if let Err(err) =
-        sync_rollout_summaries_from_memories(&root, &raw_memories, max_raw_memories).await
+        sync_rollout_summaries_from_memories(&root, &artifact_memories, artifact_memories.len())
+            .await
     {
         tracing::error!("failed syncing local memory artifacts for global consolidation: {err}");
         job::failed(session, db, &claim, "failed_sync_artifacts").await;
@@ -95,7 +105,8 @@ pub(super) async fn run(session: &Arc<Session>, config: Arc<Config>) {
     }
     // [`raw_memories.md`]
     if let Err(err) =
-        rebuild_raw_memories_file_from_memories(&root, &raw_memories, max_raw_memories).await
+        rebuild_raw_memories_file_from_memories(&root, &artifact_memories, artifact_memories.len())
+            .await
     {
         tracing::error!("failed syncing local memory artifacts for global consolidation: {err}");
         job::failed(session, db, &claim, "failed_rebuild_raw_memories").await;
@@ -103,12 +114,20 @@ pub(super) async fn run(session: &Arc<Session>, config: Arc<Config>) {
     }
     if raw_memories.is_empty() {
         // We check only after sync of the file system.
-        job::succeed(session, db, &claim, new_watermark, "succeeded_no_input").await;
+        job::succeed(
+            session,
+            db,
+            &claim,
+            new_watermark,
+            &[],
+            "succeeded_no_input",
+        )
+        .await;
         return;
     }
 
     // 5. Spawn the agent
-    let prompt = agent::get_prompt(config);
+    let prompt = agent::get_prompt(config, &selection);
     let source = SessionSource::SubAgent(SubAgentSource::MemoryConsolidation);
     let thread_id = match session
         .services
@@ -129,6 +148,7 @@ pub(super) async fn run(session: &Arc<Session>, config: Arc<Config>) {
         session,
         claim,
         new_watermark,
+        raw_memories.clone(),
         thread_id,
         phase_two_e2e_timer,
     );
@@ -140,6 +160,22 @@ pub(super) async fn run(session: &Arc<Session>, config: Arc<Config>) {
     emit_metrics(session, counters);
 }
 
+fn artifact_memories_for_phase2(
+    selection: &codex_state::Phase2InputSelection,
+) -> Vec<Stage1Output> {
+    let mut seen = HashSet::new();
+    let mut memories = selection.selected.clone();
+    for memory in &selection.selected {
+        seen.insert(rollout_summary_file_stem(memory));
+    }
+    for memory in &selection.previous_selected {
+        if seen.insert(rollout_summary_file_stem(memory)) {
+            memories.push(memory.clone());
+        }
+    }
+    memories
+}
+
 mod job {
     use super::*;
 
@@ -205,6 +241,7 @@ mod job {
         db: &StateRuntime,
         claim: &Claim,
         completion_watermark: i64,
+        selected_outputs: &[codex_state::Stage1Output],
         reason: &'static str,
     ) {
         session.services.otel_manager.counter(
@@ -213,7 +250,7 @@ mod job {
             &[("status", reason)],
         );
         let _ = db
-            .mark_global_phase2_job_succeeded(&claim.token, completion_watermark)
+            .mark_global_phase2_job_succeeded(&claim.token, completion_watermark, selected_outputs)
             .await;
     }
 }
@@ -266,9 +303,12 @@ mod agent {
         Some(agent_config)
     }
 
-    pub(super) fn get_prompt(config: Arc<Config>) -> Vec<UserInput> {
+    pub(super) fn get_prompt(
+        config: Arc<Config>,
+        selection: &codex_state::Phase2InputSelection,
+    ) -> Vec<UserInput> {
         let root = memory_root(&config.codex_home);
-        let prompt = build_consolidation_prompt(&root);
+        let prompt = build_consolidation_prompt(&root, selection);
         vec![UserInput::Text {
             text: prompt,
             text_elements: vec![],
@@ -280,6 +320,7 @@ mod agent {
         session: &Arc<Session>,
         claim: Claim,
         new_watermark: i64,
+        selected_outputs: Vec<codex_state::Stage1Output>,
         thread_id: ThreadId,
         phase_two_e2e_timer: Option<codex_otel::Timer>,
     ) {
@@ -316,7 +357,15 @@ mod agent {
                 if let Some(token_usage) = agent_control.get_total_token_usage(thread_id).await {
                     emit_token_usage_metrics(&session, &token_usage);
                 }
-                job::succeed(&session, &db, &claim, new_watermark, "succeeded").await;
+                job::succeed(
+                    &session,
+                    &db,
+                    &claim,
+                    new_watermark,
+                    &selected_outputs,
+                    "succeeded",
+                )
+                .await;
             } else {
                 job::failed(&session, &db, &claim, "failed_agent").await;
             }

codex-rs/core/src/memories/prompts.rs

@@ -1,9 +1,13 @@
 use crate::memories::memory_root;
 use crate::memories::phase_one;
+use crate::memories::storage::rollout_summary_file_stem_from_parts;
 use crate::truncate::TruncationPolicy;
 use crate::truncate::truncate_text;
 use askama::Template;
 use codex_protocol::openai_models::ModelInfo;
+use codex_state::Phase2InputSelection;
+use codex_state::Stage1Output;
+use codex_state::Stage1OutputRef;
 use std::path::Path;
 use tokio::fs;
 use tracing::warn;
@@ -12,6 +16,7 @@ use tracing::warn;
 #[template(path = "memories/consolidation.md", escape = "none")]
 struct ConsolidationPromptTemplate<'a> {
     memory_root: &'a str,
+    phase2_input_selection: &'a str,
 }
 
 #[derive(Template)]
@@ -30,17 +35,91 @@ struct MemoryToolDeveloperInstructionsTemplate<'a> {
 }
 
 /// Builds the consolidation subagent prompt for a specific memory root.
-pub(super) fn build_consolidation_prompt(memory_root: &Path) -> String {
+pub(super) fn build_consolidation_prompt(
+    memory_root: &Path,
+    selection: &Phase2InputSelection,
+) -> String {
     let memory_root = memory_root.display().to_string();
+    let phase2_input_selection = render_phase2_input_selection(selection);
     let template = ConsolidationPromptTemplate {
         memory_root: &memory_root,
+        phase2_input_selection: &phase2_input_selection,
     };
     template.render().unwrap_or_else(|err| {
         warn!("failed to render memories consolidation prompt template: {err}");
-        format!("## Memory Phase 2 (Consolidation)\nConsolidate Codex memories in: {memory_root}")
+        format!(
+            "## Memory Phase 2 (Consolidation)\nConsolidate Codex memories in: {memory_root}\n\n{phase2_input_selection}"
+        )
     })
 }
 
+fn render_phase2_input_selection(selection: &Phase2InputSelection) -> String {
+    let retained = selection.retained_thread_ids.len();
+    let added = selection.selected.len().saturating_sub(retained);
+    let selected = if selection.selected.is_empty() {
+        "- none".to_string()
+    } else {
+        selection
+            .selected
+            .iter()
+            .map(|item| {
+                render_selected_input_line(
+                    item,
+                    selection.retained_thread_ids.contains(&item.thread_id),
+                )
+            })
+            .collect::<Vec<_>>()
+            .join("\n")
+    };
+    let removed = if selection.removed.is_empty() {
+        "- none".to_string()
+    } else {
+        selection
+            .removed
+            .iter()
+            .map(render_removed_input_line)
+            .collect::<Vec<_>>()
+            .join("\n")
+    };
+
+    format!(
+        "- selected inputs this run: {}\n- newly added since the last successful Phase 2 run: {added}\n- retained from the last successful Phase 2 run: {retained}\n- removed from the last successful Phase 2 run: {}\n\nCurrent selected Phase 1 inputs:\n{selected}\n\nRemoved from the last successful Phase 2 selection:\n{removed}\n",
+        selection.selected.len(),
+        selection.removed.len(),
+    )
+}
+
+fn render_selected_input_line(item: &Stage1Output, retained: bool) -> String {
+    let status = if retained { "retained" } else { "added" };
+    let rollout_summary_file = format!(
+        "rollout_summaries/{}.md",
+        rollout_summary_file_stem_from_parts(
+            item.thread_id,
+            item.source_updated_at,
+            item.rollout_slug.as_deref(),
+        )
+    );
+    format!(
+        "- [{status}] thread_id={}, rollout_summary_file={rollout_summary_file}",
+        item.thread_id
+    )
+}
+
+fn render_removed_input_line(item: &Stage1OutputRef) -> String {
+    let rollout_summary_file = format!(
+        "rollout_summaries/{}.md",
+        rollout_summary_file_stem_from_parts(
+            item.thread_id,
+            item.source_updated_at,
+            item.rollout_slug.as_deref(),
+        )
+    );
+    format!(
+        "- thread_id={}, rollout_summary_file={rollout_summary_file}",
+        item.thread_id
+    )
+}
+
 /// Builds the stage-1 user message containing rollout metadata and content.
 ///
 /// Large rollout payloads are truncated to 70% of the active model's effective

codex-rs/core/src/memories/storage.rs

@@ -82,6 +82,8 @@ async fn rebuild_raw_memories_file(
         )
         .map_err(raw_memories_format_error)?;
         writeln!(body, "cwd: {}", memory.cwd.display()).map_err(raw_memories_format_error)?;
+        writeln!(body, "rollout_path: {}", memory.rollout_path.display())
+            .map_err(raw_memories_format_error)?;
         let rollout_summary_file = format!("{}.md", rollout_summary_file_stem(memory));
         writeln!(body, "rollout_summary_file: {rollout_summary_file}")
             .map_err(raw_memories_format_error)?;
@@ -138,7 +140,12 @@ async fn write_rollout_summary_for_thread(
         memory.source_updated_at.to_rfc3339()
     )
     .map_err(rollout_summary_format_error)?;
+    writeln!(body, "rollout_path: {}", memory.rollout_path.display())
+        .map_err(rollout_summary_format_error)?;
     writeln!(body, "cwd: {}", memory.cwd.display()).map_err(rollout_summary_format_error)?;
+    if let Some(git_branch) = memory.git_branch.as_deref() {
+        writeln!(body, "git_branch: {git_branch}").map_err(rollout_summary_format_error)?;
+    }
     writeln!(body).map_err(rollout_summary_format_error)?;
     body.push_str(&memory.rollout_summary);
     body.push('\n');
@@ -267,7 +274,9 @@ mod tests {
             raw_memory: "raw memory".to_string(),
             rollout_summary: "summary".to_string(),
             rollout_slug: rollout_slug.map(ToString::to_string),
+            rollout_path: PathBuf::from("/tmp/rollout.jsonl"),
             cwd: PathBuf::from("/tmp/workspace"),
+            git_branch: None,
             generated_at: Utc.timestamp_opt(124, 0).single().expect("timestamp"),
         }
     }

codex-rs/core/src/memories/tests.rs

@@ -86,7 +86,9 @@ async fn sync_rollout_summaries_and_raw_memories_file_keeps_latest_memories_only
         raw_memory: "raw memory".to_string(),
         rollout_summary: "short summary".to_string(),
         rollout_slug: None,
+        rollout_path: PathBuf::from("/tmp/rollout-100.jsonl"),
         cwd: PathBuf::from("/tmp/workspace"),
+        git_branch: None,
         generated_at: Utc.timestamp_opt(101, 0).single().expect("timestamp"),
     }];
 
@@ -135,6 +137,7 @@ async fn sync_rollout_summaries_and_raw_memories_file_keeps_latest_memories_only
     assert!(raw_memories.contains("raw memory"));
     assert!(raw_memories.contains(&keep_id));
     assert!(raw_memories.contains("cwd: /tmp/workspace"));
+    assert!(raw_memories.contains("rollout_path: /tmp/rollout-100.jsonl"));
     assert!(raw_memories.contains(&format!(
         "rollout_summary_file: {canonical_rollout_summary_file}"
     )));
@@ -150,6 +153,10 @@ async fn sync_rollout_summaries_and_raw_memories_file_keeps_latest_memories_only
         .find("cwd: /tmp/workspace")
         .map(|offset| thread_pos + offset)
         .expect("cwd should exist after thread header");
+    let rollout_path_pos = raw_memories[thread_pos..]
+        .find("rollout_path: /tmp/rollout-100.jsonl")
+        .map(|offset| thread_pos + offset)
+        .expect("rollout_path should exist after thread header");
     let file_pos = raw_memories[thread_pos..]
         .find(&format!(
             "rollout_summary_file: {canonical_rollout_summary_file}"
@@ -158,7 +165,8 @@ async fn sync_rollout_summaries_and_raw_memories_file_keeps_latest_memories_only
         .expect("rollout_summary_file should exist after thread header");
     assert!(thread_pos < updated_pos);
     assert!(updated_pos < cwd_pos);
-    assert!(cwd_pos < file_pos);
+    assert!(cwd_pos < rollout_path_pos);
+    assert!(rollout_path_pos < file_pos);
 }
 
 #[tokio::test]
@@ -184,7 +192,9 @@ async fn sync_rollout_summaries_uses_timestamp_hash_and_sanitized_slug_filename(
         raw_memory: "raw memory".to_string(),
         rollout_summary: "short summary".to_string(),
         rollout_slug: Some("Unsafe Slug/With Spaces & Symbols + EXTRA_LONG_12345".to_string()),
+        rollout_path: PathBuf::from("/tmp/rollout-200.jsonl"),
         cwd: PathBuf::from("/tmp/workspace"),
+        git_branch: Some("feature/memory-branch".to_string()),
         generated_at: Utc.timestamp_opt(201, 0).single().expect("timestamp"),
     }];
 
@@ -239,6 +249,8 @@ async fn sync_rollout_summaries_uses_timestamp_hash_and_sanitized_slug_filename(
         .await
         .expect("read rollout summary");
     assert!(summary.contains(&format!("thread_id: {thread_id}")));
+    assert!(summary.contains("rollout_path: /tmp/rollout-200.jsonl"));
+    assert!(summary.contains("git_branch: feature/memory-branch"));
     assert!(
         !tokio::fs::try_exists(&stale_unslugged_path)
             .await
@@ -283,7 +295,9 @@ task_outcome: success
             .to_string(),
         rollout_summary: "short summary".to_string(),
         rollout_slug: Some("Unsafe Slug/With Spaces & Symbols + EXTRA_LONG_12345".to_string()),
+        rollout_path: PathBuf::from("/tmp/rollout-200.jsonl"),
         cwd: PathBuf::from("/tmp/workspace"),
+        git_branch: None,
         generated_at: Utc.timestamp_opt(201, 0).single().expect("timestamp"),
     }];
 
@@ -316,6 +330,12 @@ task_outcome: success
     let raw_memories = tokio::fs::read_to_string(raw_memories_file(&root))
         .await
         .expect("read raw memories");
+    let summary = tokio::fs::read_to_string(
+        rollout_summaries_dir(&root).join(canonical_rollout_summary_file),
+    )
+    .await
+    .expect("read rollout summary");
+    assert!(summary.contains("rollout_path: /tmp/rollout-200.jsonl"));
     assert!(raw_memories.contains(&format!(
         "rollout_summary_file: {canonical_rollout_summary_file}"
     )));
@@ -360,7 +380,9 @@ mod phase2 {
             raw_memory: "raw memory".to_string(),
             rollout_summary: "rollout summary".to_string(),
             rollout_slug: None,
+            rollout_path: PathBuf::from("/tmp/rollout-summary.jsonl"),
             cwd: PathBuf::from("/tmp/workspace"),
+            git_branch: None,
             generated_at: chrono::DateTime::<Utc>::from_timestamp(source_updated_at + 1, 0)
                 .expect("valid generated_at timestamp"),
         }
@@ -542,7 +564,7 @@ mod phase2 {
     #[tokio::test]
     async fn dispatch_reclaims_stale_global_lock_and_starts_consolidation() {
         let harness = DispatchHarness::new().await;
-        harness.seed_stage1_output(100).await;
+        harness.seed_stage1_output(Utc::now().timestamp()).await;
 
         let stale_claim = harness
             .state_db
@@ -556,12 +578,18 @@ mod phase2 {
 
         phase2::run(&harness.session, Arc::clone(&harness.config)).await;
 
-        let running_claim = harness
+        let post_dispatch_claim = harness
             .state_db
             .try_claim_global_phase2_job(ThreadId::new(), 3_600)
             .await
-            .expect("claim while running");
-        pretty_assertions::assert_eq!(running_claim, Phase2JobClaimOutcome::SkippedRunning);
+            .expect("claim after stale lock dispatch");
+        assert!(
+            matches!(
+                post_dispatch_claim,
+                Phase2JobClaimOutcome::SkippedRunning | Phase2JobClaimOutcome::SkippedNotDirty
+            ),
+            "stale-lock dispatch should either keep the reclaimed job running or finish it before re-claim"
+        );
 
         let user_input_ops = harness.user_input_ops_count();
         pretty_assertions::assert_eq!(user_input_ops, 1);

codex-rs/core/src/models_manager/model_info.rs

@@ -1,3 +1,4 @@
+use codex_protocol::config_types::ReasoningSummary;
 use codex_protocol::openai_models::ConfigShellToolType;
 use codex_protocol::openai_models::ModelInfo;
 use codex_protocol::openai_models::ModelInstructionsVariables;
@@ -72,6 +73,7 @@ pub(crate) fn model_info_from_slug(slug: &str) -> ModelInfo {
         base_instructions: BASE_INSTRUCTIONS.to_string(),
         model_messages: local_personality_messages_for_slug(slug),
         supports_reasoning_summaries: false,
+        default_reasoning_summary: ReasoningSummary::Auto,
         support_verbosity: false,
         default_verbosity: None,
         apply_patch_tool_type: None,

codex-rs/core/src/rollout/recorder.rs

@@ -326,7 +326,9 @@ impl RolloutRecorder {
                 else {
                     break;
                 };
-                if let Some(path) = select_resume_path_from_db_page(&db_page, filter_cwd) {
+                if let Some(path) =
+                    select_resume_path_from_db_page(&db_page, filter_cwd, default_provider).await
+                {
                     return Ok(Some(path));
                 }
                 db_cursor = db_page.next_anchor.map(Into::into);
@@ -348,7 +350,7 @@ impl RolloutRecorder {
                 default_provider,
             )
             .await?;
-            if let Some(path) = select_resume_path(&page, filter_cwd) {
+            if let Some(path) = select_resume_path(&page, filter_cwd, default_provider).await {
                 return Ok(Some(path));
             }
             cursor = page.next_cursor;
@@ -961,35 +963,79 @@ impl From<codex_state::ThreadsPage> for ThreadsPage {
     }
 }
 
-fn select_resume_path(page: &ThreadsPage, filter_cwd: Option<&Path>) -> Option<PathBuf> {
+async fn select_resume_path(
+    page: &ThreadsPage,
+    filter_cwd: Option<&Path>,
+    default_provider: &str,
+) -> Option<PathBuf> {
     match filter_cwd {
-        Some(cwd) => page.items.iter().find_map(|item| {
-            if item
-                .cwd
-                .as_ref()
-                .is_some_and(|session_cwd| cwd_matches(session_cwd, cwd))
-            {
-                Some(item.path.clone())
-            } else {
-                None
+        Some(cwd) => {
+            for item in &page.items {
+                if resume_candidate_matches_cwd(
+                    item.path.as_path(),
+                    item.cwd.as_deref(),
+                    cwd,
+                    default_provider,
+                )
+                .await
+                {
+                    return Some(item.path.clone());
+                }
             }
-        }),
+            None
+        }
         None => page.items.first().map(|item| item.path.clone()),
     }
 }
 
-fn select_resume_path_from_db_page(
+async fn resume_candidate_matches_cwd(
+    rollout_path: &Path,
+    cached_cwd: Option<&Path>,
+    cwd: &Path,
+    default_provider: &str,
+) -> bool {
+    if cached_cwd.is_some_and(|session_cwd| cwd_matches(session_cwd, cwd)) {
+        return true;
+    }
+
+    if let Ok((items, _, _)) = RolloutRecorder::load_rollout_items(rollout_path).await
+        && let Some(latest_turn_context_cwd) = items.iter().rev().find_map(|item| match item {
+            RolloutItem::TurnContext(turn_context) => Some(turn_context.cwd.as_path()),
+            RolloutItem::SessionMeta(_)
+            | RolloutItem::ResponseItem(_)
+            | RolloutItem::Compacted(_)
+            | RolloutItem::EventMsg(_) => None,
+        })
+    {
+        return cwd_matches(latest_turn_context_cwd, cwd);
+    }
+
+    metadata::extract_metadata_from_rollout(rollout_path, default_provider, None)
+        .await
+        .is_ok_and(|outcome| cwd_matches(outcome.metadata.cwd.as_path(), cwd))
+}
+
+async fn select_resume_path_from_db_page(
     page: &codex_state::ThreadsPage,
     filter_cwd: Option<&Path>,
+    default_provider: &str,
 ) -> Option<PathBuf> {
     match filter_cwd {
-        Some(cwd) => page.items.iter().find_map(|item| {
-            if cwd_matches(item.cwd.as_path(), cwd) {
-                Some(item.rollout_path.clone())
-            } else {
-                None
+        Some(cwd) => {
+            for item in &page.items {
+                if resume_candidate_matches_cwd(
+                    item.rollout_path.as_path(),
+                    Some(item.cwd.as_path()),
+                    cwd,
+                    default_provider,
+                )
+                .await
+                {
+                    return Some(item.rollout_path.clone());
+                }
             }
-        }),
+            None
+        }
         None => page.items.first().map(|item| item.rollout_path.clone()),
     }
 }
@@ -1010,8 +1056,12 @@ mod tests {
     use crate::config::ConfigBuilder;
     use crate::features::Feature;
     use chrono::TimeZone;
+    use codex_protocol::config_types::ReasoningSummary as ReasoningSummaryConfig;
     use codex_protocol::protocol::AgentMessageEvent;
+    use codex_protocol::protocol::AskForApproval;
     use codex_protocol::protocol::EventMsg;
+    use codex_protocol::protocol::SandboxPolicy;
+    use codex_protocol::protocol::TurnContextItem;
     use codex_protocol::protocol::UserMessageEvent;
     use pretty_assertions::assert_eq;
     use std::fs::File;
@@ -1320,4 +1370,47 @@ mod tests {
         assert_eq!(repaired_path, Some(real_path));
         Ok(())
     }
+
+    #[tokio::test]
+    async fn resume_candidate_matches_cwd_reads_latest_turn_context() -> std::io::Result<()> {
+        let home = TempDir::new().expect("temp dir");
+        let stale_cwd = home.path().join("stale");
+        let latest_cwd = home.path().join("latest");
+        fs::create_dir_all(&stale_cwd)?;
+        fs::create_dir_all(&latest_cwd)?;
+
+        let path = write_session_file(home.path(), "2025-01-03T13-00-00", Uuid::from_u128(9012))?;
+        let mut file = std::fs::OpenOptions::new().append(true).open(&path)?;
+        let turn_context = RolloutLine {
+            timestamp: "2025-01-03T13:00:01Z".to_string(),
+            item: RolloutItem::TurnContext(TurnContextItem {
+                turn_id: Some("turn-1".to_string()),
+                cwd: latest_cwd.clone(),
+                approval_policy: AskForApproval::Never,
+                sandbox_policy: SandboxPolicy::new_read_only_policy(),
+                network: None,
+                model: "test-model".to_string(),
+                personality: None,
+                collaboration_mode: None,
+                effort: None,
+                summary: ReasoningSummaryConfig::Auto,
+                user_instructions: None,
+                developer_instructions: None,
+                final_output_json_schema: None,
+                truncation_policy: None,
+            }),
+        };
+        writeln!(file, "{}", serde_json::to_string(&turn_context)?)?;
+
+        assert!(
+            resume_candidate_matches_cwd(
+                path.as_path(),
+                Some(stale_cwd.as_path()),
+                latest_cwd.as_path(),
+                "test-provider",
+            )
+            .await
+        );
+        Ok(())
+    }
 }

codex-rs/core/src/rollout/truncation.rs

@@ -193,7 +193,7 @@ mod tests {
     #[tokio::test]
     async fn ignores_session_prefix_messages_when_truncating_rollout_from_start() {
         let (session, turn_context) = make_session_and_context().await;
-        let mut items = session.build_initial_context(&turn_context).await;
+        let mut items = session.build_initial_context(&turn_context, None).await;
         items.push(user_msg("feature request"));
         items.push(assistant_msg("ack"));
         items.push(user_msg("second question"));

codex-rs/core/src/session_prefix.rs

@@ -1,28 +1,8 @@
 use codex_protocol::protocol::AgentStatus;
 
-/// Helpers for identifying model-visible "session prefix" messages.
-///
-/// A session prefix is a user-role message that carries configuration or state needed by
-/// follow-up turns (e.g. `<environment_context>`, `<turn_aborted>`). These items are persisted in
-/// history so the model can see them, but they are not user intent and must not create user-turn
-/// boundaries.
-pub(crate) const ENVIRONMENT_CONTEXT_OPEN_TAG: &str = "<environment_context>";
-pub(crate) const TURN_ABORTED_OPEN_TAG: &str = "<turn_aborted>";
-pub(crate) const SUBAGENT_NOTIFICATION_OPEN_TAG: &str = "<subagent_notification>";
-pub(crate) const SUBAGENT_NOTIFICATION_CLOSE_TAG: &str = "</subagent_notification>";
-
-fn starts_with_ascii_case_insensitive(text: &str, prefix: &str) -> bool {
-    text.get(..prefix.len())
-        .is_some_and(|candidate| candidate.eq_ignore_ascii_case(prefix))
-}
-
-/// Returns true if `text` starts with a session prefix marker (case-insensitive).
-pub(crate) fn is_session_prefix(text: &str) -> bool {
-    let trimmed = text.trim_start();
-    starts_with_ascii_case_insensitive(trimmed, ENVIRONMENT_CONTEXT_OPEN_TAG)
-        || starts_with_ascii_case_insensitive(trimmed, TURN_ABORTED_OPEN_TAG)
-        || starts_with_ascii_case_insensitive(trimmed, SUBAGENT_NOTIFICATION_OPEN_TAG)
-}
+/// Helpers for model-visible session state markers that are stored in user-role
+/// messages but are not user intent.
+use crate::contextual_user_message::SUBAGENT_NOTIFICATION_FRAGMENT;
 
 pub(crate) fn format_subagent_notification_message(agent_id: &str, status: &AgentStatus) -> String {
     let payload_json = serde_json::json!({
@@ -30,19 +10,12 @@ pub(crate) fn format_subagent_notification_message(agent_id: &str, status: &Agen
         "status": status,
     })
     .to_string();
-    format!("{SUBAGENT_NOTIFICATION_OPEN_TAG}\n{payload_json}\n{SUBAGENT_NOTIFICATION_CLOSE_TAG}")
+    SUBAGENT_NOTIFICATION_FRAGMENT.wrap(payload_json)
 }
 
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use pretty_assertions::assert_eq;
-
-    #[test]
-    fn is_session_prefix_is_case_insensitive() {
-        assert_eq!(
-            is_session_prefix("<SUBAGENT_NOTIFICATION>{}</subagent_notification>"),
-            true
-        );
+pub(crate) fn format_subagent_context_line(agent_id: &str, agent_nickname: Option<&str>) -> String {
+    match agent_nickname.filter(|nickname| !nickname.is_empty()) {
+        Some(agent_nickname) => format!("- {agent_id}: {agent_nickname}"),
+        None => format!("- {agent_id}"),
     }
 }

codex-rs/core/src/skills/manager.rs

@@ -130,6 +130,12 @@ impl SkillsManager {
                 }),
         );
         let mut outcome = load_skills_from_roots(roots);
+        if !extra_user_roots.is_empty() {
+            // When extra user roots are provided, skip system skills before caching the result.
+            outcome
+                .skills
+                .retain(|skill| skill.scope != SkillScope::System);
+        }
         outcome.disabled_paths = disabled_paths_from_stack(&config_layer_stack);
         let (by_scripts_dir, by_doc_path) =
             build_implicit_skill_path_indexes(outcome.allowed_skills_for_implicit_invocation());

codex-rs/core/src/tasks/mod.rs

@@ -21,12 +21,12 @@ use tracing::warn;
 use crate::AuthManager;
 use crate::codex::Session;
 use crate::codex::TurnContext;
+use crate::contextual_user_message::TURN_ABORTED_OPEN_TAG;
 use crate::models_manager::manager::ModelsManager;
 use crate::protocol::EventMsg;
 use crate::protocol::TurnAbortReason;
 use crate::protocol::TurnAbortedEvent;
 use crate::protocol::TurnCompleteEvent;
-use crate::session_prefix::TURN_ABORTED_OPEN_TAG;
 use crate::state::ActiveTurn;
 use crate::state::RunningTask;
 use crate::state::TaskKind;

codex-rs/core/src/thread_manager.rs

@@ -252,7 +252,7 @@ impl ThreadManager {
     }
 
     pub async fn list_thread_ids(&self) -> Vec<ThreadId> {
-        self.state.threads.read().await.keys().copied().collect()
+        self.state.list_thread_ids().await
     }
 
     pub async fn refresh_mcp_servers(&self, refresh_config: McpServerRefreshConfig) {
@@ -412,6 +412,10 @@ impl ThreadManager {
 }
 
 impl ThreadManagerState {
+    pub(crate) async fn list_thread_ids(&self) -> Vec<ThreadId> {
+        self.threads.read().await.keys().copied().collect()
+    }
+
     /// Fetch a thread by ID or return ThreadNotFound.
     pub(crate) async fn get_thread(&self, thread_id: ThreadId) -> CodexResult<Arc<CodexThread>> {
         let threads = self.threads.read().await;
@@ -495,6 +499,27 @@ impl ThreadManagerState {
         .await
     }
 
+    pub(crate) async fn fork_thread_with_source(
+        &self,
+        config: Config,
+        initial_history: InitialHistory,
+        agent_control: AgentControl,
+        session_source: SessionSource,
+        persist_extended_history: bool,
+    ) -> CodexResult<NewThread> {
+        self.spawn_thread_with_source(
+            config,
+            initial_history,
+            Arc::clone(&self.auth_manager),
+            agent_control,
+            session_source,
+            Vec::new(),
+            persist_extended_history,
+            None,
+        )
+        .await
+    }
+
     /// Spawn a new thread with optional history and register it with the manager.
     #[allow(clippy::too_many_arguments)]
     pub(crate) async fn spawn_thread(
@@ -690,7 +715,7 @@ mod tests {
     #[tokio::test]
     async fn ignores_session_prefix_messages_when_truncating() {
         let (session, turn_context) = make_session_and_context().await;
-        let mut items = session.build_initial_context(&turn_context).await;
+        let mut items = session.build_initial_context(&turn_context, None).await;
         items.push(user_msg("feature request"));
         items.push(assistant_msg("ack"));
         items.push(user_msg("second question"));

codex-rs/core/src/tools/handlers/multi_agents.rs

@@ -91,6 +91,7 @@ impl ToolHandler for MultiAgentHandler {
 
 mod spawn {
     use super::*;
+    use crate::agent::control::SpawnAgentOptions;
     use crate::agent::role::DEFAULT_ROLE_NAME;
     use crate::agent::role::apply_role_to_config;
 
@@ -103,6 +104,8 @@ mod spawn {
         message: Option<String>,
         items: Option<Vec<UserInput>>,
         agent_type: Option<String>,
+        #[serde(default)]
+        fork_context: bool,
     }
 
     #[derive(Debug, Serialize)]
@@ -155,7 +158,7 @@ mod spawn {
         let result = session
             .services
             .agent_control
-            .spawn_agent(
+            .spawn_agent_with_options(
                 config,
                 input_items,
                 Some(thread_spawn_source(
@@ -163,6 +166,9 @@ mod spawn {
                     child_depth,
                     role_name,
                 )),
+                SpawnAgentOptions {
+                    fork_parent_spawn_call_id: args.fork_context.then(|| call_id.clone()),
+                },
             )
             .await
             .map_err(collab_spawn_error);
@@ -914,7 +920,7 @@ fn build_agent_shared_config(turn: &TurnContext) -> Result<Config, FunctionCallE
     config.model = Some(turn.model_info.slug.clone());
     config.model_provider = turn.provider.clone();
     config.model_reasoning_effort = turn.reasoning_effort;
-    config.model_reasoning_summary = turn.reasoning_summary;
+    config.model_reasoning_summary = Some(turn.reasoning_summary);
     config.developer_instructions = turn.developer_instructions.clone();
     config.compact_prompt = turn.compact_prompt.clone();
     apply_spawn_agent_runtime_overrides(&mut config, turn)?;
@@ -2046,7 +2052,7 @@ mod tests {
         expected.model = Some(turn.model_info.slug.clone());
         expected.model_provider = turn.provider.clone();
         expected.model_reasoning_effort = turn.reasoning_effort;
-        expected.model_reasoning_summary = turn.reasoning_summary;
+        expected.model_reasoning_summary = Some(turn.reasoning_summary);
         expected.developer_instructions = turn.developer_instructions.clone();
         expected.compact_prompt = turn.compact_prompt.clone();
         expected.permissions.shell_environment_policy = turn.shell_environment_policy.clone();
@@ -2098,7 +2104,7 @@ mod tests {
         expected.model = Some(turn.model_info.slug.clone());
         expected.model_provider = turn.provider.clone();
         expected.model_reasoning_effort = turn.reasoning_effort;
-        expected.model_reasoning_summary = turn.reasoning_summary;
+        expected.model_reasoning_summary = Some(turn.reasoning_summary);
         expected.developer_instructions = turn.developer_instructions.clone();
         expected.compact_prompt = turn.compact_prompt.clone();
         expected.permissions.shell_environment_policy = turn.shell_environment_policy.clone();

codex-rs/core/src/tools/js_repl/mod.rs

@@ -11,6 +11,7 @@ use std::time::Duration;
 use codex_protocol::ThreadId;
 use codex_protocol::models::ContentItem;
 use codex_protocol::models::FunctionCallOutputContentItem;
+use codex_protocol::models::FunctionCallOutputPayload;
 use codex_protocol::models::ResponseInputItem;
 use serde::Deserialize;
 use serde::Serialize;
@@ -24,6 +25,8 @@ use tokio::sync::Mutex;
 use tokio::sync::Notify;
 use tokio::sync::OnceCell;
 use tokio_util::sync::CancellationToken;
+use tracing::info;
+use tracing::trace;
 use tracing::warn;
 use uuid::Uuid;
 
@@ -39,6 +42,8 @@ use crate::sandboxing::SandboxPermissions;
 use crate::tools::ToolRouter;
 use crate::tools::context::SharedTurnDiffTracker;
 use crate::tools::sandboxing::SandboxablePreference;
+use crate::truncate::TruncationPolicy;
+use crate::truncate::truncate_text;
 
 pub(crate) const JS_REPL_PRAGMA_PREFIX: &str = "// codex-js-repl:";
 const KERNEL_SOURCE: &str = include_str!("kernel.js");
@@ -51,6 +56,7 @@ const JS_REPL_STDERR_TAIL_SEPARATOR: &str = " | ";
 const JS_REPL_EXEC_ID_LOG_LIMIT: usize = 8;
 const JS_REPL_MODEL_DIAG_STDERR_MAX_BYTES: usize = 1_024;
 const JS_REPL_MODEL_DIAG_ERROR_MAX_BYTES: usize = 256;
+const JS_REPL_TOOL_RESPONSE_TEXT_PREVIEW_MAX_BYTES: usize = 512;
 
 /// Per-task js_repl handle stored on the turn context.
 pub(crate) struct JsReplHandle {
@@ -123,6 +129,31 @@ struct ExecToolCalls {
     cancel: CancellationToken,
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[allow(clippy::enum_variant_names)]
+enum JsReplToolCallPayloadKind {
+    MessageContent,
+    FunctionText,
+    FunctionContentItems,
+    CustomText,
+    McpResult,
+    McpErrorResult,
+    Error,
+}
+
+#[derive(Debug, Clone, Default, PartialEq, Eq)]
+struct JsReplToolCallResponseSummary {
+    response_type: Option<String>,
+    payload_kind: Option<JsReplToolCallPayloadKind>,
+    payload_text_preview: Option<String>,
+    payload_text_length: Option<usize>,
+    payload_item_count: Option<usize>,
+    text_item_count: Option<usize>,
+    image_item_count: Option<usize>,
+    structured_content_present: Option<bool>,
+    result_is_error: Option<bool>,
+}
+
 enum KernelStreamEnd {
     Shutdown,
     StdoutEof,
@@ -404,6 +435,198 @@ impl JsReplManager {
         }
     }
 
+    fn log_tool_call_response(
+        req: &RunToolRequest,
+        ok: bool,
+        summary: &JsReplToolCallResponseSummary,
+        response: Option<&JsonValue>,
+        error: Option<&str>,
+    ) {
+        info!(
+            exec_id = %req.exec_id,
+            tool_call_id = %req.id,
+            tool_name = %req.tool_name,
+            ok,
+            summary = ?summary,
+            "js_repl nested tool call completed"
+        );
+        if let Some(response) = response {
+            trace!(
+                exec_id = %req.exec_id,
+                tool_call_id = %req.id,
+                tool_name = %req.tool_name,
+                response_json = %response,
+                "js_repl nested tool call raw response"
+            );
+        }
+        if let Some(error) = error {
+            trace!(
+                exec_id = %req.exec_id,
+                tool_call_id = %req.id,
+                tool_name = %req.tool_name,
+                error = %error,
+                "js_repl nested tool call raw error"
+            );
+        }
+    }
+
+    fn summarize_text_payload(
+        response_type: Option<&str>,
+        payload_kind: JsReplToolCallPayloadKind,
+        text: &str,
+    ) -> JsReplToolCallResponseSummary {
+        JsReplToolCallResponseSummary {
+            response_type: response_type.map(str::to_owned),
+            payload_kind: Some(payload_kind),
+            payload_text_preview: (!text.is_empty()).then(|| {
+                truncate_text(
+                    text,
+                    TruncationPolicy::Bytes(JS_REPL_TOOL_RESPONSE_TEXT_PREVIEW_MAX_BYTES),
+                )
+            }),
+            payload_text_length: Some(text.len()),
+            ..Default::default()
+        }
+    }
+
+    fn summarize_function_output_payload(
+        response_type: &str,
+        payload_kind: JsReplToolCallPayloadKind,
+        output: &FunctionCallOutputPayload,
+    ) -> JsReplToolCallResponseSummary {
+        let (payload_item_count, text_item_count, image_item_count) =
+            if let Some(items) = output.content_items() {
+                let text_item_count = items
+                    .iter()
+                    .filter(|item| matches!(item, FunctionCallOutputContentItem::InputText { .. }))
+                    .count();
+                let image_item_count = items.len().saturating_sub(text_item_count);
+                (
+                    Some(items.len()),
+                    Some(text_item_count),
+                    Some(image_item_count),
+                )
+            } else {
+                (None, None, None)
+            };
+        let payload_text = output.body.to_text();
+        JsReplToolCallResponseSummary {
+            response_type: Some(response_type.to_string()),
+            payload_kind: Some(payload_kind),
+            payload_text_preview: payload_text.as_deref().and_then(|text| {
+                (!text.is_empty()).then(|| {
+                    truncate_text(
+                        text,
+                        TruncationPolicy::Bytes(JS_REPL_TOOL_RESPONSE_TEXT_PREVIEW_MAX_BYTES),
+                    )
+                })
+            }),
+            payload_text_length: payload_text.as_ref().map(String::len),
+            payload_item_count,
+            text_item_count,
+            image_item_count,
+            ..Default::default()
+        }
+    }
+
+    fn summarize_message_payload(content: &[ContentItem]) -> JsReplToolCallResponseSummary {
+        let text_item_count = content
+            .iter()
+            .filter(|item| {
+                matches!(
+                    item,
+                    ContentItem::InputText { .. } | ContentItem::OutputText { .. }
+                )
+            })
+            .count();
+        let image_item_count = content.len().saturating_sub(text_item_count);
+        let payload_text = content
+            .iter()
+            .filter_map(|item| match item {
+                ContentItem::InputText { text } | ContentItem::OutputText { text }
+                    if !text.trim().is_empty() =>
+                {
+                    Some(text.as_str())
+                }
+                ContentItem::InputText { .. }
+                | ContentItem::InputImage { .. }
+                | ContentItem::OutputText { .. } => None,
+            })
+            .collect::<Vec<_>>();
+        let payload_text = if payload_text.is_empty() {
+            None
+        } else {
+            Some(payload_text.join("\n"))
+        };
+        JsReplToolCallResponseSummary {
+            response_type: Some("message".to_string()),
+            payload_kind: Some(JsReplToolCallPayloadKind::MessageContent),
+            payload_text_preview: payload_text.as_deref().and_then(|text| {
+                (!text.is_empty()).then(|| {
+                    truncate_text(
+                        text,
+                        TruncationPolicy::Bytes(JS_REPL_TOOL_RESPONSE_TEXT_PREVIEW_MAX_BYTES),
+                    )
+                })
+            }),
+            payload_text_length: payload_text.as_ref().map(String::len),
+            payload_item_count: Some(content.len()),
+            text_item_count: Some(text_item_count),
+            image_item_count: Some(image_item_count),
+            ..Default::default()
+        }
+    }
+
+    fn summarize_tool_call_response(response: &ResponseInputItem) -> JsReplToolCallResponseSummary {
+        match response {
+            ResponseInputItem::Message { content, .. } => Self::summarize_message_payload(content),
+            ResponseInputItem::FunctionCallOutput { output, .. } => {
+                let payload_kind = if output.content_items().is_some() {
+                    JsReplToolCallPayloadKind::FunctionContentItems
+                } else {
+                    JsReplToolCallPayloadKind::FunctionText
+                };
+                Self::summarize_function_output_payload(
+                    "function_call_output",
+                    payload_kind,
+                    output,
+                )
+            }
+            ResponseInputItem::CustomToolCallOutput { output, .. } => Self::summarize_text_payload(
+                Some("custom_tool_call_output"),
+                JsReplToolCallPayloadKind::CustomText,
+                output,
+            ),
+            ResponseInputItem::McpToolCallOutput { result, .. } => match result {
+                Ok(result) => {
+                    let output = FunctionCallOutputPayload::from(result);
+                    let mut summary = Self::summarize_function_output_payload(
+                        "mcp_tool_call_output",
+                        JsReplToolCallPayloadKind::McpResult,
+                        &output,
+                    );
+                    summary.payload_item_count = Some(result.content.len());
+                    summary.structured_content_present = Some(result.structured_content.is_some());
+                    summary.result_is_error = Some(result.is_error.unwrap_or(false));
+                    summary
+                }
+                Err(error) => {
+                    let mut summary = Self::summarize_text_payload(
+                        Some("mcp_tool_call_output"),
+                        JsReplToolCallPayloadKind::McpErrorResult,
+                        error,
+                    );
+                    summary.result_is_error = Some(true);
+                    summary
+                }
+            },
+        }
+    }
+
+    fn summarize_tool_call_error(error: &str) -> JsReplToolCallResponseSummary {
+        Self::summarize_text_payload(None, JsReplToolCallPayloadKind::Error, error)
+    }
+
     pub async fn reset(&self) -> Result<(), FunctionCallError> {
         let _permit = self.exec_lock.clone().acquire_owned().await.map_err(|_| {
             FunctionCallError::RespondToModel("js_repl execution unavailable".to_string())
@@ -1006,11 +1229,14 @@ impl JsReplManager {
 
     async fn run_tool_request(exec: ExecContext, req: RunToolRequest) -> RunToolResult {
         if is_js_repl_internal_tool(&req.tool_name) {
+            let error = "js_repl cannot invoke itself".to_string();
+            let summary = Self::summarize_tool_call_error(&error);
+            Self::log_tool_call_response(&req, false, &summary, None, Some(&error));
             return RunToolResult {
                 id: req.id,
                 ok: false,
                 response: None,
-                error: Some("js_repl cannot invoke itself".to_string()),
+                error: Some(error),
             };
         }
 
@@ -1109,27 +1335,41 @@ impl JsReplManager {
                     }
                 }
 
+                let summary = Self::summarize_tool_call_response(&response);
                 match serde_json::to_value(response) {
-                    Ok(value) => RunToolResult {
-                        id: req.id,
-                        ok: true,
-                        response: Some(value),
-                        error: None,
-                    },
-                    Err(err) => RunToolResult {
-                        id: req.id,
-                        ok: false,
-                        response: None,
-                        error: Some(format!("failed to serialize tool output: {err}")),
-                    },
+                    Ok(value) => {
+                        Self::log_tool_call_response(&req, true, &summary, Some(&value), None);
+                        RunToolResult {
+                            id: req.id,
+                            ok: true,
+                            response: Some(value),
+                            error: None,
+                        }
+                    }
+                    Err(err) => {
+                        let error = format!("failed to serialize tool output: {err}");
+                        let summary = Self::summarize_tool_call_error(&error);
+                        Self::log_tool_call_response(&req, false, &summary, None, Some(&error));
+                        RunToolResult {
+                            id: req.id,
+                            ok: false,
+                            response: None,
+                            error: Some(error),
+                        }
+                    }
+                }
+            }
+            Err(err) => {
+                let error = err.to_string();
+                let summary = Self::summarize_tool_call_error(&error);
+                Self::log_tool_call_response(&req, false, &summary, None, Some(&error));
+                RunToolResult {
+                    id: req.id,
+                    ok: false,
+                    response: None,
+                    error: Some(error),
                 }
             }
-            Err(err) => RunToolResult {
-                id: req.id,
-                ok: false,
-                response: None,
-                error: Some(err.to_string()),
-            },
         }
     }
 
@@ -1362,6 +1602,8 @@ mod tests {
     use codex_protocol::dynamic_tools::DynamicToolResponse;
     use codex_protocol::dynamic_tools::DynamicToolSpec;
     use codex_protocol::models::ContentItem;
+    use codex_protocol::models::FunctionCallOutputContentItem;
+    use codex_protocol::models::FunctionCallOutputPayload;
     use codex_protocol::models::ResponseInputItem;
     use codex_protocol::openai_models::InputModality;
     use pretty_assertions::assert_eq;
@@ -1579,6 +1821,55 @@ mod tests {
         );
     }
 
+    #[test]
+    fn summarize_tool_call_response_for_multimodal_function_output() {
+        let response = ResponseInputItem::FunctionCallOutput {
+            call_id: "call-1".to_string(),
+            output: FunctionCallOutputPayload::from_content_items(vec![
+                FunctionCallOutputContentItem::InputImage {
+                    image_url: "data:image/png;base64,abcd".to_string(),
+                },
+            ]),
+        };
+
+        let actual = JsReplManager::summarize_tool_call_response(&response);
+
+        assert_eq!(
+            actual,
+            JsReplToolCallResponseSummary {
+                response_type: Some("function_call_output".to_string()),
+                payload_kind: Some(JsReplToolCallPayloadKind::FunctionContentItems),
+                payload_text_preview: None,
+                payload_text_length: None,
+                payload_item_count: Some(1),
+                text_item_count: Some(0),
+                image_item_count: Some(1),
+                structured_content_present: None,
+                result_is_error: None,
+            }
+        );
+    }
+
+    #[test]
+    fn summarize_tool_call_error_marks_error_payload() {
+        let actual = JsReplManager::summarize_tool_call_error("tool failed");
+
+        assert_eq!(
+            actual,
+            JsReplToolCallResponseSummary {
+                response_type: None,
+                payload_kind: Some(JsReplToolCallPayloadKind::Error),
+                payload_text_preview: Some("tool failed".to_string()),
+                payload_text_length: Some("tool failed".len()),
+                payload_item_count: None,
+                text_item_count: None,
+                image_item_count: None,
+                structured_content_present: None,
+                result_is_error: None,
+            }
+        );
+    }
+
     #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
     async fn reset_clears_inflight_exec_tool_calls_without_waiting() {
         let manager = JsReplManager::new(None, Vec::new())

codex-rs/core/src/tools/spec.rs

@@ -633,6 +633,15 @@ fn create_spawn_agent_tool(config: &ToolsConfig) -> ToolSpec {
                 )),
             },
         ),
+        (
+            "fork_context".to_string(),
+            JsonSchema::Boolean {
+                description: Some(
+                    "When true, fork the current thread history into the new agent before sending the initial prompt. This must be used when you want the new agent to have exactly the same context as you."
+                        .to_string(),
+                ),
+            },
+        ),
     ]);
 
     ToolSpec::Function(ResponsesApiTool {

codex-rs/core/src/user_shell_command.rs

@@ -1,21 +1,12 @@
 use std::time::Duration;
 
-use codex_protocol::models::ContentItem;
 use codex_protocol::models::ResponseItem;
 
 use crate::codex::TurnContext;
+use crate::contextual_user_message::USER_SHELL_COMMAND_FRAGMENT;
 use crate::exec::ExecToolCallOutput;
 use crate::tools::format_exec_output_str;
 
-pub const USER_SHELL_COMMAND_OPEN: &str = "<user_shell_command>";
-pub const USER_SHELL_COMMAND_CLOSE: &str = "</user_shell_command>";
-
-pub fn is_user_shell_command_text(text: &str) -> bool {
-    let trimmed = text.trim_start();
-    let lowered = trimmed.to_ascii_lowercase();
-    lowered.starts_with(USER_SHELL_COMMAND_OPEN)
-}
-
 fn format_duration_line(duration: Duration) -> String {
     let duration_seconds = duration.as_secs_f64();
     format!("Duration: {duration_seconds:.4} seconds")
@@ -48,7 +39,7 @@ pub fn format_user_shell_command_record(
     turn_context: &TurnContext,
 ) -> String {
     let body = format_user_shell_command_body(command, exec_output, turn_context);
-    format!("{USER_SHELL_COMMAND_OPEN}\n{body}\n{USER_SHELL_COMMAND_CLOSE}")
+    USER_SHELL_COMMAND_FRAGMENT.wrap(body)
 }
 
 pub fn user_shell_command_record_item(
@@ -56,15 +47,11 @@ pub fn user_shell_command_record_item(
     exec_output: &ExecToolCallOutput,
     turn_context: &TurnContext,
 ) -> ResponseItem {
-    ResponseItem::Message {
-        id: None,
-        role: "user".to_string(),
-        content: vec![ContentItem::InputText {
-            text: format_user_shell_command_record(command, exec_output, turn_context),
-        }],
-        end_turn: None,
-        phase: None,
-    }
+    USER_SHELL_COMMAND_FRAGMENT.into_message(format_user_shell_command_record(
+        command,
+        exec_output,
+        turn_context,
+    ))
 }
 
 #[cfg(test)]
@@ -72,14 +59,16 @@ mod tests {
     use super::*;
     use crate::codex::make_session_and_context;
     use crate::exec::StreamOutput;
+    use codex_protocol::models::ContentItem;
     use pretty_assertions::assert_eq;
 
     #[test]
     fn detects_user_shell_command_text_variants() {
-        assert!(is_user_shell_command_text(
-            "<user_shell_command>\necho hi\n</user_shell_command>"
-        ));
-        assert!(!is_user_shell_command_text("echo hi"));
+        assert!(
+            USER_SHELL_COMMAND_FRAGMENT
+                .matches_text("<user_shell_command>\necho hi\n</user_shell_command>")
+        );
+        assert!(!USER_SHELL_COMMAND_FRAGMENT.matches_text("echo hi"));
     }
 
     #[tokio::test]

codex-rs/core/templates/memories/consolidation.md

@@ -106,7 +106,7 @@ Under `{{ memory_root }}/`:
     context.
   - source of rollout-level metadata needed for MEMORY.md `### rollout_summary_files`
     annotations;
-    you should be able to find `cwd` and `updated_at` there.
+    you should be able to find `cwd`, `rollout_path`, and `updated_at` there.
 - `MEMORY.md`
   - merged memories; produce a lightly clustered version if applicable
 - `rollout_summaries/*.md`
@@ -121,6 +121,27 @@ Mode selection:
 - INCREMENTAL UPDATE: existing artifacts already exist and `raw_memories.md`
   mostly contains new additions.
 
+Incremental thread diff snapshot (computed before the current artifact sync rewrites local files):
+
+**Diff since last consolidation:**
+{{ phase2_input_selection }}
+
+Incremental update and forgetting mechanism:
+- Use the diff provided
+- Do not open raw sessions / original rollout transcripts.
+- For each added thread id, search it in `raw_memories.md`, read that raw-memory section, and
+  read the corresponding `rollout_summaries/*.md` file only when needed for stronger evidence,
+  task placement, or conflict resolution.
+- For each removed thread id, search it in `MEMORY.md` and delete only the memory supported by
+  that thread. Use `thread_id=<thread_id>` in `### rollout_summary_files` when available; if not,
+  fall back to rollout summary filenames plus the corresponding `rollout_summaries/*.md` files.
+- If a `MEMORY.md` block contains both removed and undeleted threads, do not delete the whole
+  block. Remove only the removed thread's references and thread-local learnings, preserve shared
+  or still-supported content, and split or rewrite the block only if needed to keep the undeleted
+  threads intact.
+- After `MEMORY.md` cleanup is done, revisit `memory_summary.md` and remove or rewrite stale
+  summary/index content that was only supported by removed thread ids.
+
 Outputs:
 Under `{{ memory_root }}/`:
 A) `MEMORY.md`
@@ -171,7 +192,7 @@ Required task-oriented body shape (strict):
 ## Task 1: <task description, outcome>
 
 ### rollout_summary_files
-- <rollout_summaries/file1.md> (cwd=<path>, updated_at=<timestamp>, thread_id=<thread_id>, <optional status/usefulness note>)
+- <rollout_summaries/file1.md> (cwd=<path>, rollout_path=<path>, updated_at=<timestamp>, thread_id=<thread_id>, <optional status/usefulness note>)
 
 ### keywords
 
@@ -236,7 +257,8 @@ Schema rules (strict):
   - Every `## Task <n>` section must include `### rollout_summary_files`, `### keywords`,
     and `### learnings`.
   - `### rollout_summary_files` must be task-local (not a block-wide catch-all list).
-  - Each rollout annotation must include `cwd=<path>` and `updated_at=<timestamp>`.
+  - Each rollout annotation must include `cwd=<path>`, `rollout_path=<path>`, and
+    `updated_at=<timestamp>`.
     If missing from a rollout summary, recover them from `raw_memories.md`.
   - Major learnings should be traceable to rollout summaries listed in the same task section.
   - Order rollout references by freshness and practical usefulness.
@@ -497,27 +519,42 @@ WORKFLOW
      conflicting task families until MEMORY blocks are richer and more useful than raw memories
 
 3) INCREMENTAL UPDATE behavior:
-   - Treat `raw_memories.md` as the primary source of NEW signal.
-   - Read existing memory files first for continuity.
+   - Read existing `MEMORY.md` and `memory_summary.md` first for continuity and to locate
+     existing references that may need surgical cleanup.
+   - Use the injected thread-diff snapshot as the first routing pass:
+     - added thread ids = ingestion queue
+     - removed thread ids = forgetting / stale-cleanup queue
    - Build an index of rollout references already present in existing `MEMORY.md` before
      scanning raw memories so you can route net-new evidence into the right blocks.
-   - Compute net-new candidates from the raw-memory inventory (threads / rollout summaries /
-     updated evidence not already represented in `MEMORY.md`).
+   - Work in this order:
+     1. For newly added thread ids, search them in `raw_memories.md`, read those sections, and
+        open the corresponding `rollout_summaries/*.md` files when necessary.
+     2. Route the new signal into existing `MEMORY.md` blocks or create new ones when needed.
+     3. For removed thread ids, search `MEMORY.md` and surgically delete or rewrite only the
+        unsupported thread-local memory.
+     4. If a block mixes removed and undeleted threads, preserve the undeleted-thread content;
+        split or rewrite the block if that is the cleanest way to delete only the removed part.
+     5. After `MEMORY.md` is correct, revisit `memory_summary.md` and remove or rewrite stale
+        summary/index content that no longer has undeleted support.
    - Integrate new signal into existing artifacts by:
-     - scanning new raw memories in recency order and identifying which existing blocks they should update
+     - scanning the newly added raw-memory entries in recency order and identifying which existing blocks they should update
      - updating existing knowledge with better/newer evidence
      - updating stale or contradicting guidance
+     - pruning or downgrading memory whose only provenance comes from removed thread ids
      - expanding terse old blocks when new summaries/raw memories make the task family clearer
      - doing light clustering and merging if needed
      - refreshing `MEMORY.md` top-of-file ordering so recent high-utility task families stay easy to find
      - rebuilding the `memory_summary.md` recent active window (last 3 memory days) from current `updated_at` coverage
      - updating existing skills or adding new skills only when there is clear new reusable procedure
-     - update `memory_summary.md` last to reflect the final state of the memory folder
+     - updating `memory_summary.md` last to reflect the final state of the memory folder
    - Minimize churn in incremental mode: if an existing `MEMORY.md` block or `## What's in Memory`
      topic still reflects the current evidence and points to the same task family / retrieval
      target, keep its wording, label, and relative order mostly stable. Rewrite/reorder/rename/
      split/merge only when fixing a real problem (staleness, ambiguity, schema drift, wrong
      boundaries) or when meaningful new evidence materially improves retrieval clarity/searchability.
+   - Spend most of your deep-dive budget on newly added thread ids and on mixed blocks touched by
+     removed thread ids. Do not re-read unchanged older threads unless you need them for
+     conflict resolution, clustering, or provenance repair.
 
 4) Evidence deep-dive rule (both modes):
    - `raw_memories.md` is the routing layer, not always the final authority for detail.
@@ -528,6 +565,9 @@ WORKFLOW
    - When a task family is important, ambiguous, or duplicated across multiple rollouts,
      open the relevant `rollout_summaries/*.md` files and extract richer procedural detail,
      validation signals, and user feedback before finalizing `MEMORY.md`.
+   - When deleting stale memory from a mixed block, use the relevant rollout summaries to decide
+     which details are uniquely supported by removed threads versus still supported by undeleted
+     threads.
    - Use `updated_at` and validation strength together to resolve stale/conflicting notes.
 
 5) For both modes, update `MEMORY.md` after skill updates:
@@ -541,6 +581,8 @@ WORKFLOW
 7) Final pass:
   - remove duplication in memory_summary, skills/, and MEMORY.md
   - remove stale or low-signal blocks that are less likely to be useful in the future
+  - remove or rewrite blocks/task sections whose supporting rollout references point only to
+    removed thread ids or missing rollout summary files
   - run a global rollout-reference audit on final `MEMORY.md` and fix accidental duplicate
     entries / redundant repetition, while preserving intentional multi-task or multi-block
     reuse when it adds distinct task-local value
@@ -559,16 +601,3 @@ WORKFLOW
 
 You should dive deep and make sure you didn't miss any important information that might
 be useful for future agents; do not be superficial.
-
-============================================================
-SEARCH / REVIEW COMMANDS (RG-FIRST)
-============================================================
-
-Use `rg` for fast retrieval while consolidating:
-
-- Search durable notes:
-  `rg -n -i "<pattern>" "{{ memory_root }}/MEMORY.md"`
-- Search across memory tree:
-  `rg -n -i "<pattern>" "{{ memory_root }}" | head -n 100`
-- Locate rollout summary files:
-  `rg --files "{{ memory_root }}/rollout_summaries" | head -n 400`

codex-rs/core/templates/memories/read_path.md

@@ -25,7 +25,10 @@ Memory layout (general -> specific):
   - scripts/ (optional helper scripts)
   - examples/ (optional example outputs)
   - templates/ (optional templates)
-- {{ base_path }}/rollout_summaries/ (per-rollout recaps + evidence snippets)
+ - {{ base_path }}/rollout_summaries/ (per-rollout recaps + evidence snippets)
+  - The paths of these entries can be found in {{ base_path }}/MEMORY.md or {{ base_path }}/rollout_summaries/ as `rollout_path`
+  - These files are append-only `jsonl`: `session_meta.payload.id` identifies the session, `turn_context` marks turn boundaries, `event_msg` is the lightweight status stream, and `response_item` contains actual messages, tool calls, and tool outputs.
+  - For efficient lookup, prefer matching the filename suffix or `session_meta.payload.id`; avoid broad full-content scans unless needed.
 
 Quick memory pass (when applicable):
 
@@ -34,7 +37,8 @@ Quick memory pass (when applicable):
 3. Only if MEMORY.md directly points to rollout summaries/skills, open the 1-2
    most relevant files under {{ base_path }}/rollout_summaries/ or
    {{ base_path }}/skills/.
-4. If there are no relevant hits, stop memory lookup and continue normally.
+4. If above are not clear and you need exact commands, error text, or precise evidence, search over `rollout_path` for more evidence.
+5. If there are no relevant hits, stop memory lookup and continue normally.
 
 Quick-pass budget:
 

codex-rs/core/tests/common/context_snapshot.rs

@@ -62,7 +62,7 @@ pub fn format_response_items_snapshot(items: &[Value], options: &ContextSnapshot
             match item_type {
                 "message" => {
                     let role = item.get("role").and_then(Value::as_str).unwrap_or("unknown");
-                    let text = item
+                    let rendered_parts = item
                         .get("content")
                         .and_then(Value::as_array)
                         .map(|content| {
@@ -93,11 +93,27 @@ pub fn format_response_items_snapshot(items: &[Value], options: &ContextSnapshot
                                     }
                                 })
                                 .collect::<Vec<String>>()
-                                .join(" | ")
                         })
-                        .filter(|text| !text.is_empty())
-                        .unwrap_or_else(|| "<NO_TEXT>".to_string());
-                    format!("{idx:02}:message/{role}:{text}")
+                        .unwrap_or_default();
+                    let role = if rendered_parts.len() > 1 {
+                        format!("{role}[{}]", rendered_parts.len())
+                    } else {
+                        role.to_string()
+                    };
+                    if rendered_parts.is_empty() {
+                        return format!("{idx:02}:message/{role}:<NO_TEXT>");
+                    }
+                    if rendered_parts.len() == 1 {
+                        return format!("{idx:02}:message/{role}:{}", rendered_parts[0]);
+                    }
+
+                    let parts = rendered_parts
+                        .iter()
+                        .enumerate()
+                        .map(|(part_idx, part)| format!("    [{:02}] {part}", part_idx + 1))
+                        .collect::<Vec<String>>()
+                        .join("\n");
+                    format!("{idx:02}:message/{role}:\n{parts}")
                 }
                 "function_call" => {
                     let name = item.get("name").and_then(Value::as_str).unwrap_or("unknown");
@@ -222,15 +238,34 @@ fn canonicalize_snapshot_text(text: &str) -> String {
         return "<AGENTS_MD>".to_string();
     }
     if text.starts_with("<environment_context>") {
+        let subagent_count = text
+            .split_once("<subagents>")
+            .and_then(|(_, rest)| rest.split_once("</subagents>"))
+            .map(|(subagents, _)| {
+                subagents
+                    .lines()
+                    .filter(|line| line.trim_start().starts_with("- "))
+                    .count()
+            })
+            .unwrap_or(0);
+        let subagents_suffix = if subagent_count > 0 {
+            format!(":subagents={subagent_count}")
+        } else {
+            String::new()
+        };
         if let (Some(cwd_start), Some(cwd_end)) = (text.find("<cwd>"), text.find("</cwd>")) {
             let cwd = &text[cwd_start + "<cwd>".len()..cwd_end];
             return if cwd.ends_with("PRETURN_CONTEXT_DIFF_CWD") {
-                "<ENVIRONMENT_CONTEXT:cwd=PRETURN_CONTEXT_DIFF_CWD>".to_string()
+                format!("<ENVIRONMENT_CONTEXT:cwd=PRETURN_CONTEXT_DIFF_CWD{subagents_suffix}>")
             } else {
-                "<ENVIRONMENT_CONTEXT:cwd=<CWD>>".to_string()
+                format!("<ENVIRONMENT_CONTEXT:cwd=<CWD>{subagents_suffix}>")
             };
         }
-        return "<ENVIRONMENT_CONTEXT>".to_string();
+        return if subagent_count > 0 {
+            format!("<ENVIRONMENT_CONTEXT{subagents_suffix}>")
+        } else {
+            "<ENVIRONMENT_CONTEXT>".to_string()
+        };
     }
     if text.starts_with("You are performing a CONTEXT CHECKPOINT COMPACTION.") {
         return "<SUMMARIZATION_PROMPT>".to_string();
@@ -258,7 +293,7 @@ mod tests {
             "role": "user",
             "content": [{
                 "type": "input_text",
-                "text": "# AGENTS.md instructions for /tmp/example"
+                "text": "# AGENTS.md instructions for /tmp/example\n\n<INSTRUCTIONS>\nbody\n</INSTRUCTIONS>"
             }]
         })];
 
@@ -269,7 +304,7 @@ mod tests {
 
         assert_eq!(
             rendered,
-            "00:message/user:# AGENTS.md instructions for /tmp/example"
+            r"00:message/user:# AGENTS.md instructions for /tmp/example\n\n<INSTRUCTIONS>\nbody\n</INSTRUCTIONS>"
         );
     }
 
@@ -280,7 +315,7 @@ mod tests {
             "role": "user",
             "content": [{
                 "type": "input_text",
-                "text": "# AGENTS.md instructions for /tmp/example"
+                "text": "# AGENTS.md instructions for /tmp/example\n\n<INSTRUCTIONS>\nbody\n</INSTRUCTIONS>"
             }]
         })];
 
@@ -292,6 +327,28 @@ mod tests {
         assert_eq!(rendered, "00:message/user:<AGENTS_MD>");
     }
 
+    #[test]
+    fn redacted_text_mode_normalizes_environment_context_with_subagents() {
+        let items = vec![json!({
+            "type": "message",
+            "role": "user",
+            "content": [{
+                "type": "input_text",
+                "text": "<environment_context>\n  <cwd>/tmp/example</cwd>\n  <shell>bash</shell>\n  <subagents>\n    - agent-1: atlas\n    - agent-2\n  </subagents>\n</environment_context>"
+            }]
+        })];
+
+        let rendered = format_response_items_snapshot(
+            &items,
+            &ContextSnapshotOptions::default().render_mode(ContextSnapshotRenderMode::RedactedText),
+        );
+
+        assert_eq!(
+            rendered,
+            "00:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>:subagents=2>"
+        );
+    }
+
     #[test]
     fn image_only_message_is_rendered_as_non_text_span() {
         let items = vec![json!({
@@ -333,7 +390,7 @@ mod tests {
 
         assert_eq!(
             rendered,
-            "00:message/user:<image> | <input_image:image_url> | </image>"
+            "00:message/user[3]:\n    [01] <image>\n    [02] <input_image:image_url>\n    [03] </image>"
         );
     }
 }

codex-rs/core/tests/common/responses.rs

@@ -141,6 +141,32 @@ impl ResponsesRequest {
             .collect()
     }
 
+    /// Returns `input_text` spans grouped by `message` input for the provided role.
+    pub fn message_input_text_groups(&self, role: &str) -> Vec<Vec<String>> {
+        self.inputs_of_type("message")
+            .into_iter()
+            .filter(|item| item.get("role").and_then(Value::as_str) == Some(role))
+            .filter_map(|item| item.get("content").and_then(Value::as_array).cloned())
+            .map(|content| {
+                content
+                    .into_iter()
+                    .filter(|span| span.get("type").and_then(Value::as_str) == Some("input_text"))
+                    .filter_map(|span| span.get("text").and_then(Value::as_str).map(str::to_owned))
+                    .collect()
+            })
+            .collect()
+    }
+
+    pub fn has_message_with_input_texts(
+        &self,
+        role: &str,
+        predicate: impl Fn(&[String]) -> bool,
+    ) -> bool {
+        self.message_input_text_groups(role)
+            .iter()
+            .any(|texts| predicate(texts))
+    }
+
     /// Returns all `input_image` `image_url` spans from `message` inputs for the provided role.
     pub fn message_input_image_urls(&self, role: &str) -> Vec<String> {
         self.inputs_of_type("message")

codex-rs/core/tests/responses_headers.rs

@@ -111,7 +111,14 @@ async fn responses_stream_includes_subagent_header_on_review() {
     }];
 
     let mut stream = client_session
-        .stream(&prompt, &model_info, &otel_manager, effort, summary, None)
+        .stream(
+            &prompt,
+            &model_info,
+            &otel_manager,
+            effort,
+            summary.unwrap_or(model_info.default_reasoning_summary),
+            None,
+        )
         .await
         .expect("stream failed");
     while let Some(event) = stream.next().await {
@@ -216,7 +223,14 @@ async fn responses_stream_includes_subagent_header_on_other() {
     }];
 
     let mut stream = client_session
-        .stream(&prompt, &model_info, &otel_manager, effort, summary, None)
+        .stream(
+            &prompt,
+            &model_info,
+            &otel_manager,
+            effort,
+            summary.unwrap_or(model_info.default_reasoning_summary),
+            None,
+        )
         .await
         .expect("stream failed");
     while let Some(event) = stream.next().await {
@@ -267,7 +281,7 @@ async fn responses_respects_model_info_overrides_from_config() {
     config.model_provider_id = provider.name.clone();
     config.model_provider = provider.clone();
     config.model_supports_reasoning_summaries = Some(true);
-    config.model_reasoning_summary = ReasoningSummary::Detailed;
+    config.model_reasoning_summary = Some(ReasoningSummary::Detailed);
     let effort = config.model_reasoning_effort;
     let summary = config.model_reasoning_summary;
     let model = config.model.clone().expect("model configured");
@@ -320,7 +334,14 @@ async fn responses_respects_model_info_overrides_from_config() {
     }];
 
     let mut stream = client_session
-        .stream(&prompt, &model_info, &otel_manager, effort, summary, None)
+        .stream(
+            &prompt,
+            &model_info,
+            &otel_manager,
+            effort,
+            summary.unwrap_or(model_info.default_reasoning_summary),
+            None,
+        )
         .await
         .expect("stream failed");
     while let Some(event) = stream.next().await {

codex-rs/core/tests/suite/client.rs

@@ -31,6 +31,7 @@ use codex_protocol::models::ReasoningItemContent;
 use codex_protocol::models::ReasoningItemReasoningSummary;
 use codex_protocol::models::ResponseItem;
 use codex_protocol::models::WebSearchAction;
+use codex_protocol::openai_models::ModelsResponse;
 use codex_protocol::openai_models::ReasoningEffort;
 use codex_protocol::protocol::EventMsg;
 use codex_protocol::protocol::Op;
@@ -74,40 +75,14 @@ fn assert_message_role(request_body: &serde_json::Value, role: &str) {
     assert_eq!(request_body["role"].as_str().unwrap(), role);
 }
 
-#[expect(clippy::expect_used)]
-fn assert_message_equals(request_body: &serde_json::Value, text: &str) {
-    let content = request_body["content"][0]["text"]
-        .as_str()
-        .expect("invalid message content");
-
-    assert_eq!(
-        content, text,
-        "expected message content '{content}' to equal '{text}'"
-    );
-}
-
-#[expect(clippy::expect_used)]
-fn assert_message_starts_with(request_body: &serde_json::Value, text: &str) {
-    let content = request_body["content"][0]["text"]
-        .as_str()
-        .expect("invalid message content");
-
-    assert!(
-        content.starts_with(text),
-        "expected message content '{content}' to start with '{text}'"
-    );
-}
-
-#[expect(clippy::expect_used)]
-fn assert_message_ends_with(request_body: &serde_json::Value, text: &str) {
-    let content = request_body["content"][0]["text"]
-        .as_str()
-        .expect("invalid message content");
-
-    assert!(
-        content.ends_with(text),
-        "expected message content '{content}' to end with '{text}'"
-    );
+#[expect(clippy::unwrap_used)]
+fn message_input_texts(item: &serde_json::Value) -> Vec<&str> {
+    item["content"]
+        .as_array()
+        .unwrap()
+        .iter()
+        .filter_map(|entry| entry.get("text").and_then(|text| text.as_str()))
+        .collect()
 }
 
 /// Writes an `auth.json` into the provided `codex_home` with the specified parameters.
@@ -305,19 +280,15 @@ async fn resume_includes_initial_messages_and_sends_prior_items() {
     let request = resp_mock.single_request();
     let request_body = request.body_json();
     let input = request_body["input"].as_array().expect("input array");
-    let messages: Vec<(String, String)> = input
-        .iter()
-        .filter_map(|item| {
-            let role = item.get("role")?.as_str()?;
-            let text = item
-                .get("content")?
-                .as_array()?
-                .first()?
-                .get("text")?
-                .as_str()?;
-            Some((role.to_string(), text.to_string()))
-        })
-        .collect();
+    let mut messages: Vec<(String, String)> = Vec::new();
+    for item in input {
+        let Some(role) = item.get("role").and_then(|role| role.as_str()) else {
+            continue;
+        };
+        for text in message_input_texts(item) {
+            messages.push((role.to_string(), text.to_string()));
+        }
+    }
     let pos_prior_user = messages
         .iter()
         .position(|(role, text)| role == "user" && text == "resumed user message")
@@ -354,8 +325,7 @@ async fn resume_includes_initial_messages_and_sends_prior_items() {
         .position(|(role, text)| {
             role == "user"
                 && text.contains("be nice")
-                && (text.starts_with("# AGENTS.md instructions for ")
-                    || text.starts_with("<user_instructions>"))
+                && (text.starts_with("# AGENTS.md instructions for "))
         })
         .expect("user instructions");
     let pos_environment = messages
@@ -664,16 +634,27 @@ async fn includes_user_instructions_message_in_request() {
     );
 
     assert_message_role(&request_body["input"][1], "user");
-    assert_message_starts_with(&request_body["input"][1], "# AGENTS.md instructions for ");
-    assert_message_ends_with(&request_body["input"][1], "</INSTRUCTIONS>");
-    let ui_text = request_body["input"][1]["content"][0]["text"]
-        .as_str()
+    let user_context_texts = message_input_texts(&request_body["input"][1]);
+    assert!(
+        user_context_texts
+            .iter()
+            .any(|text| text.starts_with("# AGENTS.md instructions for ")),
+        "expected AGENTS text in contextual user message, got {user_context_texts:?}"
+    );
+    let ui_text = user_context_texts
+        .iter()
+        .copied()
+        .find(|text| text.contains("<INSTRUCTIONS>"))
         .expect("invalid message content");
     assert!(ui_text.contains("<INSTRUCTIONS>"));
     assert!(ui_text.contains("be nice"));
-    assert_message_role(&request_body["input"][2], "user");
-    assert_message_starts_with(&request_body["input"][2], "<environment_context>");
-    assert_message_ends_with(&request_body["input"][2], "</environment_context>");
+    assert!(
+        user_context_texts
+            .iter()
+            .any(|text| text.starts_with("<environment_context>")
+                && text.ends_with("</environment_context>")),
+        "expected environment context in contextual user message, got {user_context_texts:?}"
+    );
 }
 
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
@@ -727,10 +708,14 @@ async fn includes_apps_guidance_as_developer_message_when_enabled() {
             && item
                 .get("content")
                 .and_then(|value| value.as_array())
-                .and_then(|value| value.first())
-                .and_then(|value| value.get("text"))
-                .and_then(|value| value.as_str())
-                .is_some_and(|text| text.contains(apps_snippet))
+                .is_some_and(|content| {
+                    content.iter().any(|entry| {
+                        entry
+                            .get("text")
+                            .and_then(|value| value.as_str())
+                            .is_some_and(|text| text.contains(apps_snippet))
+                    })
+                })
     });
     assert!(
         has_developer_apps_guidance,
@@ -742,10 +727,14 @@ async fn includes_apps_guidance_as_developer_message_when_enabled() {
             && item
                 .get("content")
                 .and_then(|value| value.as_array())
-                .and_then(|value| value.first())
-                .and_then(|value| value.get("text"))
-                .and_then(|value| value.as_str())
-                .is_some_and(|text| text.contains(apps_snippet))
+                .is_some_and(|content| {
+                    content.iter().any(|entry| {
+                        entry
+                            .get("text")
+                            .and_then(|value| value.as_str())
+                            .is_some_and(|text| text.contains(apps_snippet))
+                    })
+                })
     });
     assert!(
         !has_user_apps_guidance,
@@ -992,7 +981,9 @@ async fn user_turn_collaboration_mode_overrides_model_and_effort() -> anyhow::Re
             sandbox_policy: config.permissions.sandbox_policy.get().clone(),
             model: session_configured.model.clone(),
             effort: Some(ReasoningEffort::Low),
-            summary: config.model_reasoning_summary,
+            summary: config
+                .model_reasoning_summary
+                .unwrap_or(ReasoningSummary::Auto),
             collaboration_mode: Some(collaboration_mode),
             final_output_json_schema: None,
             personality: None,
@@ -1026,7 +1017,7 @@ async fn configured_reasoning_summary_is_sent() -> anyhow::Result<()> {
     .await;
     let TestCodex { codex, .. } = test_codex()
         .with_config(|config| {
-            config.model_reasoning_summary = ReasoningSummary::Concise;
+            config.model_reasoning_summary = Some(ReasoningSummary::Concise);
         })
         .build(&server)
         .await?;
@@ -1070,7 +1061,7 @@ async fn reasoning_summary_is_omitted_when_disabled() -> anyhow::Result<()> {
     .await;
     let TestCodex { codex, .. } = test_codex()
         .with_config(|config| {
-            config.model_reasoning_summary = ReasoningSummary::None;
+            config.model_reasoning_summary = Some(ReasoningSummary::None);
         })
         .build(&server)
         .await?;
@@ -1101,6 +1092,60 @@ async fn reasoning_summary_is_omitted_when_disabled() -> anyhow::Result<()> {
     Ok(())
 }
 
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn reasoning_summary_none_overrides_model_catalog_default() -> anyhow::Result<()> {
+    skip_if_no_network!(Ok(()));
+    let server = MockServer::start().await;
+
+    let resp_mock = mount_sse_once(
+        &server,
+        sse(vec![ev_response_created("resp1"), ev_completed("resp1")]),
+    )
+    .await;
+
+    let mut model_catalog: ModelsResponse =
+        serde_json::from_str(include_str!("../../models.json")).expect("valid models.json");
+    let model = model_catalog
+        .models
+        .iter_mut()
+        .find(|model| model.slug == "gpt-5.1")
+        .expect("gpt-5.1 exists in bundled models.json");
+    model.supports_reasoning_summaries = true;
+    model.default_reasoning_summary = ReasoningSummary::Detailed;
+
+    let TestCodex { codex, .. } = test_codex()
+        .with_model("gpt-5.1")
+        .with_config(move |config| {
+            config.model_reasoning_summary = Some(ReasoningSummary::None);
+            config.model_catalog = Some(model_catalog);
+        })
+        .build(&server)
+        .await?;
+
+    codex
+        .submit(Op::UserInput {
+            items: vec![UserInput::Text {
+                text: "hello".into(),
+                text_elements: Vec::new(),
+            }],
+            final_output_json_schema: None,
+        })
+        .await
+        .unwrap();
+
+    wait_for_event(&codex, |ev| matches!(ev, EventMsg::TurnComplete(_))).await;
+
+    let request_body = resp_mock.single_request().body_json();
+    pretty_assertions::assert_eq!(
+        request_body
+            .get("reasoning")
+            .and_then(|reasoning| reasoning.get("summary")),
+        None
+    );
+
+    Ok(())
+}
+
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn includes_default_verbosity_in_request() -> anyhow::Result<()> {
     skip_if_no_network!(Ok(()));
@@ -1283,19 +1328,42 @@ async fn includes_developer_instructions_message_in_request() {
         "expected permissions message to mention sandbox_mode, got {permissions_text:?}"
     );
 
-    assert_message_role(&request_body["input"][1], "developer");
-    assert_message_equals(&request_body["input"][1], "be useful");
-    assert_message_role(&request_body["input"][2], "user");
-    assert_message_starts_with(&request_body["input"][2], "# AGENTS.md instructions for ");
-    assert_message_ends_with(&request_body["input"][2], "</INSTRUCTIONS>");
-    let ui_text = request_body["input"][2]["content"][0]["text"]
-        .as_str()
+    let developer_messages: Vec<&serde_json::Value> = request_body["input"]
+        .as_array()
+        .expect("input array")
+        .iter()
+        .filter(|item| item.get("role").and_then(|role| role.as_str()) == Some("developer"))
+        .collect();
+    assert!(
+        developer_messages
+            .iter()
+            .any(|item| message_input_texts(item).contains(&"be useful")),
+        "expected developer instructions in a developer message, got {:?}",
+        request_body["input"]
+    );
+
+    assert_message_role(&request_body["input"][1], "user");
+    let user_context_texts = message_input_texts(&request_body["input"][1]);
+    assert!(
+        user_context_texts
+            .iter()
+            .any(|text| text.starts_with("# AGENTS.md instructions for ")),
+        "expected AGENTS text in contextual user message, got {user_context_texts:?}"
+    );
+    let ui_text = user_context_texts
+        .iter()
+        .copied()
+        .find(|text| text.contains("<INSTRUCTIONS>"))
         .expect("invalid message content");
     assert!(ui_text.contains("<INSTRUCTIONS>"));
     assert!(ui_text.contains("be nice"));
-    assert_message_role(&request_body["input"][3], "user");
-    assert_message_starts_with(&request_body["input"][3], "<environment_context>");
-    assert_message_ends_with(&request_body["input"][3], "</environment_context>");
+    assert!(
+        user_context_texts
+            .iter()
+            .any(|text| text.starts_with("<environment_context>")
+                && text.ends_with("</environment_context>")),
+        "expected environment context in contextual user message, got {user_context_texts:?}"
+    );
 }
 
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
@@ -1430,7 +1498,14 @@ async fn azure_responses_request_includes_store_and_reasoning_ids() {
     });
 
     let mut stream = client_session
-        .stream(&prompt, &model_info, &otel_manager, effort, summary, None)
+        .stream(
+            &prompt,
+            &model_info,
+            &otel_manager,
+            effort,
+            summary.unwrap_or(ReasoningSummary::Auto),
+            None,
+        )
         .await
         .expect("responses stream to start");
 

codex-rs/core/tests/suite/collaboration_instructions.rs

@@ -169,7 +169,10 @@ async fn collaboration_instructions_added_on_user_turn() -> Result<()> {
             sandbox_policy: test.config.permissions.sandbox_policy.get().clone(),
             model: test.session_configured.model.clone(),
             effort: None,
-            summary: test.config.model_reasoning_summary,
+            summary: test
+                .config
+                .model_reasoning_summary
+                .unwrap_or(codex_protocol::config_types::ReasoningSummary::Auto),
             collaboration_mode: Some(collaboration_mode),
             final_output_json_schema: None,
             personality: None,
@@ -275,7 +278,10 @@ async fn user_turn_overrides_collaboration_instructions_after_override() -> Resu
             sandbox_policy: test.config.permissions.sandbox_policy.get().clone(),
             model: test.session_configured.model.clone(),
             effort: None,
-            summary: test.config.model_reasoning_summary,
+            summary: test
+                .config
+                .model_reasoning_summary
+                .unwrap_or(codex_protocol::config_types::ReasoningSummary::Auto),
             collaboration_mode: Some(turn_mode),
             final_output_json_schema: None,
             personality: None,

codex-rs/core/tests/suite/compact.rs

@@ -756,16 +756,40 @@ async fn multiple_auto_compact_per_task_runs_after_token_limit_hit() {
     let body = requests_payloads[0].body_json();
     let input = body.get("input").and_then(|v| v.as_array()).unwrap();
 
+    fn strip_agents_parts_from_user_message(
+        value: &serde_json::Value,
+    ) -> Option<serde_json::Value> {
+        let content = value
+            .get("content")
+            .and_then(|content| content.as_array())?;
+        let filtered_content = content
+            .iter()
+            .filter(|item| {
+                !item
+                    .get("text")
+                    .and_then(|text| text.as_str())
+                    .is_some_and(|text| text.starts_with("# AGENTS.md instructions for "))
+            })
+            .cloned()
+            .collect::<Vec<_>>();
+        if filtered_content.is_empty() {
+            return None;
+        }
+        let mut normalized = value.clone();
+        normalized["content"] = serde_json::Value::Array(filtered_content);
+        Some(normalized)
+    }
+
     fn normalize_inputs(values: &[serde_json::Value]) -> Vec<serde_json::Value> {
         values
             .iter()
-            .filter(|value| {
+            .filter_map(|value| {
                 if value
                     .get("type")
                     .and_then(|ty| ty.as_str())
                     .is_some_and(|ty| ty == "function_call_output")
                 {
-                    return false;
+                    return None;
                 }
 
                 let text = value
@@ -781,11 +805,13 @@ async fn multiple_auto_compact_per_task_runs_after_token_limit_hit() {
                 if role == Some("developer")
                     && text.is_some_and(|text| text.contains("`sandbox_mode`"))
                 {
-                    return false;
+                    return None;
                 }
-                !text.is_some_and(|text| text.starts_with("# AGENTS.md instructions for "))
+                if role == Some("user") {
+                    return strip_agents_parts_from_user_message(value);
+                }
+                Some(value.clone())
             })
-            .cloned()
             .collect()
     }
 
@@ -3184,7 +3210,7 @@ async fn snapshot_request_shape_pre_turn_compaction_context_window_exceeded() {
     ]);
     let mut responses = vec![first_turn];
     responses.extend(
-        (0..6).map(|_| {
+        (0..5).map(|_| {
             sse_failed(
                 "compact-failed",
                 "context_length_exceeded",

codex-rs/core/tests/suite/memories.rs

@@ -0,0 +1,289 @@
+use anyhow::Result;
+use chrono::Duration as ChronoDuration;
+use chrono::Utc;
+use codex_core::features::Feature;
+use codex_protocol::ThreadId;
+use codex_protocol::protocol::EventMsg;
+use codex_protocol::protocol::Op;
+use codex_protocol::protocol::SessionSource;
+use core_test_support::responses::ResponseMock;
+use core_test_support::responses::ResponsesRequest;
+use core_test_support::responses::ev_assistant_message;
+use core_test_support::responses::ev_completed;
+use core_test_support::responses::ev_response_created;
+use core_test_support::responses::mount_sse_once;
+use core_test_support::responses::sse;
+use core_test_support::responses::start_mock_server;
+use core_test_support::test_codex::TestCodex;
+use core_test_support::test_codex::test_codex;
+use core_test_support::wait_for_event;
+use pretty_assertions::assert_eq;
+use std::path::Path;
+use std::sync::Arc;
+use tempfile::TempDir;
+use tokio::time::Duration;
+use tokio::time::Instant;
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn memories_startup_phase2_tracks_added_and_removed_inputs_across_runs() -> Result<()> {
+    let server = start_mock_server().await;
+    let home = Arc::new(TempDir::new()?);
+    let db = init_state_db(&home).await?;
+
+    let now = Utc::now();
+    let thread_a = seed_stage1_output(
+        db.as_ref(),
+        home.path(),
+        now - ChronoDuration::hours(2),
+        "raw memory A",
+        "rollout summary A",
+        "rollout-a",
+    )
+    .await?;
+
+    let first_phase2 = mount_sse_once(
+        &server,
+        sse(vec![
+            ev_response_created("resp-phase2-1"),
+            ev_assistant_message("msg-phase2-1", "phase2 complete"),
+            ev_completed("resp-phase2-1"),
+        ]),
+    )
+    .await;
+
+    let first = build_test_codex(&server, home.clone()).await?;
+    let first_request = wait_for_single_request(&first_phase2).await;
+    let first_prompt = phase2_prompt_text(&first_request);
+    assert!(
+        first_prompt.contains("- selected inputs this run: 1"),
+        "expected selected count in first prompt: {first_prompt}"
+    );
+    assert!(
+        first_prompt.contains("- newly added since the last successful Phase 2 run: 1"),
+        "expected added count in first prompt: {first_prompt}"
+    );
+    assert!(
+        first_prompt.contains("- removed from the last successful Phase 2 run: 0"),
+        "expected removed count in first prompt: {first_prompt}"
+    );
+    assert!(
+        first_prompt.contains(&format!("- [added] thread_id={thread_a},")),
+        "expected thread A to be marked added: {first_prompt}"
+    );
+    assert!(
+        first_prompt.contains("Removed from the last successful Phase 2 selection:\n- none"),
+        "expected no removed items in first prompt: {first_prompt}"
+    );
+
+    wait_for_phase2_success(db.as_ref(), thread_a).await?;
+    let memory_root = home.path().join("memories");
+    let raw_memories = tokio::fs::read_to_string(memory_root.join("raw_memories.md")).await?;
+    assert!(raw_memories.contains("raw memory A"));
+    assert!(!raw_memories.contains("raw memory B"));
+    let rollout_summaries = read_rollout_summary_bodies(&memory_root).await?;
+    assert_eq!(rollout_summaries.len(), 1);
+    assert!(rollout_summaries[0].contains("rollout summary A"));
+    assert!(rollout_summaries[0].contains("git_branch: branch-rollout-a"));
+
+    shutdown_test_codex(&first).await?;
+
+    let thread_b = seed_stage1_output(
+        db.as_ref(),
+        home.path(),
+        now - ChronoDuration::hours(1),
+        "raw memory B",
+        "rollout summary B",
+        "rollout-b",
+    )
+    .await?;
+
+    let second_phase2 = mount_sse_once(
+        &server,
+        sse(vec![
+            ev_response_created("resp-phase2-2"),
+            ev_assistant_message("msg-phase2-2", "phase2 complete"),
+            ev_completed("resp-phase2-2"),
+        ]),
+    )
+    .await;
+
+    let second = build_test_codex(&server, home.clone()).await?;
+    let second_request = wait_for_single_request(&second_phase2).await;
+    let second_prompt = phase2_prompt_text(&second_request);
+    assert!(
+        second_prompt.contains("- selected inputs this run: 1"),
+        "expected selected count in second prompt: {second_prompt}"
+    );
+    assert!(
+        second_prompt.contains("- newly added since the last successful Phase 2 run: 1"),
+        "expected added count in second prompt: {second_prompt}"
+    );
+    assert!(
+        second_prompt.contains("- removed from the last successful Phase 2 run: 1"),
+        "expected removed count in second prompt: {second_prompt}"
+    );
+    assert!(
+        second_prompt.contains(&format!("- [added] thread_id={thread_b},")),
+        "expected thread B to be marked added: {second_prompt}"
+    );
+    assert!(
+        second_prompt.contains(&format!("- thread_id={thread_a},")),
+        "expected thread A to be marked removed: {second_prompt}"
+    );
+
+    wait_for_phase2_success(db.as_ref(), thread_b).await?;
+    let raw_memories = tokio::fs::read_to_string(memory_root.join("raw_memories.md")).await?;
+    assert!(raw_memories.contains("raw memory B"));
+    assert!(raw_memories.contains("raw memory A"));
+    let rollout_summaries = read_rollout_summary_bodies(&memory_root).await?;
+    assert_eq!(rollout_summaries.len(), 2);
+    assert!(
+        rollout_summaries
+            .iter()
+            .any(|summary| summary.contains("rollout summary B"))
+    );
+    assert!(
+        rollout_summaries
+            .iter()
+            .any(|summary| summary.contains("git_branch: branch-rollout-b"))
+    );
+    assert!(
+        rollout_summaries
+            .iter()
+            .any(|summary| summary.contains("rollout summary A"))
+    );
+
+    shutdown_test_codex(&second).await?;
+    Ok(())
+}
+
+async fn build_test_codex(server: &wiremock::MockServer, home: Arc<TempDir>) -> Result<TestCodex> {
+    let mut builder = test_codex().with_home(home).with_config(|config| {
+        config.features.enable(Feature::Sqlite);
+        config.features.enable(Feature::MemoryTool);
+        config.memories.max_raw_memories_for_global = 1;
+    });
+    builder.build(server).await
+}
+
+async fn init_state_db(home: &Arc<TempDir>) -> Result<Arc<codex_state::StateRuntime>> {
+    let db =
+        codex_state::StateRuntime::init(home.path().to_path_buf(), "test-provider".into(), None)
+            .await?;
+    db.mark_backfill_complete(None).await?;
+    Ok(db)
+}
+
+async fn seed_stage1_output(
+    db: &codex_state::StateRuntime,
+    codex_home: &Path,
+    updated_at: chrono::DateTime<Utc>,
+    raw_memory: &str,
+    rollout_summary: &str,
+    rollout_slug: &str,
+) -> Result<ThreadId> {
+    let thread_id = ThreadId::new();
+    let mut metadata_builder = codex_state::ThreadMetadataBuilder::new(
+        thread_id,
+        codex_home.join(format!("rollout-{thread_id}.jsonl")),
+        updated_at,
+        SessionSource::Cli,
+    );
+    metadata_builder.cwd = codex_home.join(format!("workspace-{rollout_slug}"));
+    metadata_builder.model_provider = Some("test-provider".to_string());
+    metadata_builder.git_branch = Some(format!("branch-{rollout_slug}"));
+    let metadata = metadata_builder.build("test-provider");
+    db.upsert_thread(&metadata).await?;
+
+    let claim = db
+        .try_claim_stage1_job(
+            thread_id,
+            ThreadId::new(),
+            updated_at.timestamp(),
+            3_600,
+            64,
+        )
+        .await?;
+    let ownership_token = match claim {
+        codex_state::Stage1JobClaimOutcome::Claimed { ownership_token } => ownership_token,
+        other => panic!("unexpected stage-1 claim outcome: {other:?}"),
+    };
+
+    assert!(
+        db.mark_stage1_job_succeeded(
+            thread_id,
+            &ownership_token,
+            updated_at.timestamp(),
+            raw_memory,
+            rollout_summary,
+            Some(rollout_slug),
+        )
+        .await?,
+        "stage-1 success should enqueue global consolidation"
+    );
+
+    Ok(thread_id)
+}
+
+async fn wait_for_single_request(mock: &ResponseMock) -> ResponsesRequest {
+    let deadline = Instant::now() + Duration::from_secs(10);
+    loop {
+        let requests = mock.requests();
+        if let Some(request) = requests.into_iter().next() {
+            return request;
+        }
+        assert!(
+            Instant::now() < deadline,
+            "timed out waiting for phase2 request"
+        );
+        tokio::time::sleep(Duration::from_millis(50)).await;
+    }
+}
+
+#[allow(clippy::expect_used)]
+fn phase2_prompt_text(request: &ResponsesRequest) -> String {
+    request
+        .message_input_texts("user")
+        .into_iter()
+        .find(|text| text.contains("Current selected Phase 1 inputs:"))
+        .expect("phase2 prompt text")
+}
+
+async fn wait_for_phase2_success(
+    db: &codex_state::StateRuntime,
+    expected_thread_id: ThreadId,
+) -> Result<()> {
+    let deadline = Instant::now() + Duration::from_secs(10);
+    loop {
+        let selection = db.get_phase2_input_selection(1, 30).await?;
+        if selection.selected.len() == 1
+            && selection.selected[0].thread_id == expected_thread_id
+            && selection.retained_thread_ids == vec![expected_thread_id]
+            && selection.removed.is_empty()
+        {
+            return Ok(());
+        }
+
+        assert!(
+            Instant::now() < deadline,
+            "timed out waiting for phase2 success for {expected_thread_id}"
+        );
+        tokio::time::sleep(Duration::from_millis(50)).await;
+    }
+}
+
+async fn read_rollout_summary_bodies(memory_root: &Path) -> Result<Vec<String>> {
+    let mut dir = tokio::fs::read_dir(memory_root.join("rollout_summaries")).await?;
+    let mut summaries = Vec::new();
+    while let Some(entry) = dir.next_entry().await? {
+        summaries.push(tokio::fs::read_to_string(entry.path()).await?);
+    }
+    summaries.sort();
+    Ok(summaries)
+}
+
+async fn shutdown_test_codex(test: &TestCodex) -> Result<()> {
+    test.codex.submit(Op::Shutdown {}).await?;
+    wait_for_event(&test.codex, |ev| matches!(ev, EventMsg::ShutdownComplete)).await;
+    Ok(())
+}

codex-rs/core/tests/suite/mod.rs

@@ -83,6 +83,7 @@ mod json_result;
 mod list_dir;
 mod live_cli;
 mod live_reload;
+mod memories;
 mod model_info_overrides;
 mod model_overrides;
 mod model_switching;

codex-rs/core/tests/suite/model_switching.rs

@@ -234,6 +234,7 @@ async fn model_change_from_image_to_text_strips_prior_image_content() -> Result<
         base_instructions: "base instructions".to_string(),
         model_messages: None,
         supports_reasoning_summaries: false,
+        default_reasoning_summary: ReasoningSummary::Auto,
         support_verbosity: false,
         default_verbosity: None,
         apply_patch_tool_type: None,
@@ -391,6 +392,7 @@ async fn model_switch_to_smaller_model_updates_token_context_window() -> Result<
         base_instructions: "base instructions".to_string(),
         model_messages: None,
         supports_reasoning_summaries: false,
+        default_reasoning_summary: ReasoningSummary::Auto,
         support_verbosity: false,
         default_verbosity: None,
         apply_patch_tool_type: None,

codex-rs/core/tests/suite/model_visible_layout.rs

@@ -26,6 +26,7 @@ use core_test_support::responses::start_mock_server;
 use core_test_support::skip_if_no_network;
 use core_test_support::test_codex::test_codex;
 use core_test_support::wait_for_event;
+use serde_json::json;
 
 const PRETURN_CONTEXT_DIFF_CWD: &str = "PRETURN_CONTEXT_DIFF_CWD";
 
@@ -53,6 +54,30 @@ fn agents_message_count(request: &ResponsesRequest) -> usize {
         .count()
 }
 
+fn format_environment_context_subagents_snapshot(subagents: &[&str]) -> String {
+    let subagents_block = if subagents.is_empty() {
+        String::new()
+    } else {
+        let lines = subagents
+            .iter()
+            .map(|line| format!("    {line}"))
+            .collect::<Vec<_>>()
+            .join("\n");
+        format!("\n  <subagents>\n{lines}\n  </subagents>")
+    };
+    let items = vec![json!({
+        "type": "message",
+        "role": "user",
+        "content": [{
+            "type": "input_text",
+            "text": format!(
+                "<environment_context>\n  <cwd>/tmp/example</cwd>\n  <shell>bash</shell>{subagents_block}\n</environment_context>"
+            ),
+        }],
+    })];
+    context_snapshot::format_response_items_snapshot(items.as_slice(), &context_snapshot_options())
+}
+
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn snapshot_model_visible_layout_turn_overrides() -> Result<()> {
     skip_if_no_network!(Ok(()));
@@ -445,3 +470,23 @@ async fn snapshot_model_visible_layout_resume_override_matches_rollout_model() -
 
     Ok(())
 }
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn snapshot_model_visible_layout_environment_context_includes_one_subagent() -> Result<()> {
+    insta::assert_snapshot!(
+        "model_visible_layout_environment_context_includes_one_subagent",
+        format_environment_context_subagents_snapshot(&["- agent-1: Atlas"])
+    );
+
+    Ok(())
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn snapshot_model_visible_layout_environment_context_includes_two_subagents() -> Result<()> {
+    insta::assert_snapshot!(
+        "model_visible_layout_environment_context_includes_two_subagents",
+        format_environment_context_subagents_snapshot(&["- agent-1: Atlas", "- agent-2: Juniper"])
+    );
+
+    Ok(())
+}

codex-rs/core/tests/suite/models_cache_ttl.rs

@@ -336,6 +336,7 @@ fn test_remote_model(slug: &str, priority: i32) -> ModelInfo {
         base_instructions: "base instructions".to_string(),
         model_messages: None,
         supports_reasoning_summaries: false,
+        default_reasoning_summary: ReasoningSummary::Auto,
         support_verbosity: false,
         default_verbosity: None,
         apply_patch_tool_type: None,

codex-rs/core/tests/suite/personality.rs

@@ -599,6 +599,7 @@ async fn remote_model_friendly_personality_instructions_with_feature() -> anyhow
             }),
         }),
         supports_reasoning_summaries: false,
+        default_reasoning_summary: ReasoningSummary::Auto,
         support_verbosity: false,
         default_verbosity: None,
         apply_patch_tool_type: None,
@@ -706,6 +707,7 @@ async fn user_turn_personality_remote_model_template_includes_update_message() -
             }),
         }),
         supports_reasoning_summaries: false,
+        default_reasoning_summary: ReasoningSummary::Auto,
         support_verbosity: false,
         default_verbosity: None,
         apply_patch_tool_type: None,

codex-rs/core/tests/suite/prompt_caching.rs

@@ -30,10 +30,17 @@ use pretty_assertions::assert_eq;
 use tempfile::TempDir;
 
 fn text_user_input(text: String) -> serde_json::Value {
+    text_user_input_parts(vec![text])
+}
+
+fn text_user_input_parts(texts: Vec<String>) -> serde_json::Value {
     serde_json::json!({
         "type": "message",
         "role": "user",
-        "content": [ { "type": "input_text", "text": text } ]
+        "content": texts
+            .into_iter()
+            .map(|text| serde_json::json!({ "type": "input_text", "text": text }))
+            .collect::<Vec<_>>()
     })
 }
 
@@ -297,8 +304,8 @@ async fn prefixes_context_and_instructions_once_and_consistently_across_requests
     let input1 = body1["input"].as_array().expect("input array");
     assert_eq!(
         input1.len(),
-        4,
-        "expected permissions + cached prefix + env + user msg"
+        3,
+        "expected permissions + cached contextual user prefix + user msg"
     );
 
     let ui_text = input1[1]["content"][0]["text"]
@@ -313,11 +320,11 @@ async fn prefixes_context_and_instructions_once_and_consistently_across_requests
     let cwd_str = config.cwd.to_string_lossy();
     let expected_env_text = default_env_context_str(&cwd_str, &shell);
     assert_eq!(
-        input1[2],
-        text_user_input(expected_env_text),
-        "expected environment context after UI message"
+        input1[1]["content"][1]["text"].as_str(),
+        Some(expected_env_text.as_str()),
+        "expected environment context bundled after UI message in cached contextual message"
     );
-    assert_eq!(input1[3], text_user_input("hello 1".to_string()));
+    assert_eq!(input1[2], text_user_input("hello 1".to_string()));
 
     let body2 = req2.single_request().body_json();
     let input2 = body2["input"].as_array().expect("input array");
@@ -402,8 +409,10 @@ async fn overrides_turn_context_but_keeps_cached_prefix_and_key_constant() -> an
         .await?;
     wait_for_event(&codex, |ev| matches!(ev, EventMsg::TurnComplete(_))).await;
 
-    let body1 = req1.single_request().body_json();
-    let body2 = req2.single_request().body_json();
+    let request1 = req1.single_request();
+    let request2 = req2.single_request();
+    let body1 = request1.body_json();
+    let body2 = request2.body_json();
     // prompt_cache_key should remain constant across overrides
     assert_eq!(
         body1["prompt_cache_key"], body2["prompt_cache_key"],
@@ -500,11 +509,14 @@ async fn override_before_first_turn_emits_environment_context() -> anyhow::Resul
     let env_texts: Vec<&str> = input
         .iter()
         .filter_map(|msg| {
-            msg["content"]
-                .as_array()
-                .and_then(|content| content.first())
-                .and_then(|item| item["text"].as_str())
+            msg["content"].as_array().map(|content| {
+                content
+                    .iter()
+                    .filter_map(|item| item["text"].as_str())
+                    .collect::<Vec<_>>()
+            })
         })
+        .flatten()
         .filter(|text| text.starts_with(ENVIRONMENT_CONTEXT_OPEN_TAG))
         .collect();
     assert!(
@@ -559,11 +571,14 @@ async fn override_before_first_turn_emits_environment_context() -> anyhow::Resul
     let user_texts: Vec<&str> = input
         .iter()
         .filter_map(|msg| {
-            msg["content"]
-                .as_array()
-                .and_then(|content| content.first())
-                .and_then(|item| item["text"].as_str())
+            msg["content"].as_array().map(|content| {
+                content
+                    .iter()
+                    .filter_map(|item| item["text"].as_str())
+                    .collect::<Vec<_>>()
+            })
         })
+        .flatten()
         .collect();
     assert!(
         user_texts.contains(&"first message"),
@@ -639,8 +654,10 @@ async fn per_turn_overrides_keep_cached_prefix_and_key_constant() -> anyhow::Res
         .await?;
     wait_for_event(&codex, |ev| matches!(ev, EventMsg::TurnComplete(_))).await;
 
-    let body1 = req1.single_request().body_json();
-    let body2 = req2.single_request().body_json();
+    let request1 = req1.single_request();
+    let request2 = req2.single_request();
+    let body1 = request1.body_json();
+    let body2 = request2.body_json();
 
     // prompt_cache_key should remain constant across per-turn overrides
     assert_eq!(
@@ -672,26 +689,24 @@ async fn per_turn_overrides_keep_cached_prefix_and_key_constant() -> anyhow::Res
     });
     let expected_permissions_msg = body1["input"][0].clone();
     let body1_input = body1["input"].as_array().expect("input array");
-    let expected_model_switch_msg = body2["input"][body1_input.len()].clone();
+    let expected_settings_update_msg = body2["input"][body1_input.len()].clone();
+    assert_ne!(
+        expected_settings_update_msg, expected_permissions_msg,
+        "expected updated permissions message after per-turn override"
+    );
     assert_eq!(
-        expected_model_switch_msg["role"].as_str(),
+        expected_settings_update_msg["role"].as_str(),
         Some("developer")
     );
     assert!(
-        expected_model_switch_msg["content"][0]["text"]
-            .as_str()
-            .is_some_and(|text| text.contains("<model_switch>")),
-        "expected model switch message after model override: {expected_model_switch_msg:?}"
-    );
-    let expected_permissions_msg_2 = body2["input"][body1_input.len() + 2].clone();
-    assert_ne!(
-        expected_permissions_msg_2, expected_permissions_msg,
-        "expected updated permissions message after per-turn override"
+        request2.has_message_with_input_texts("developer", |texts| {
+            texts.iter().any(|text| text.contains("<model_switch>"))
+        }),
+        "expected model switch section after model override: {expected_settings_update_msg:?}"
     );
     let mut expected_body2 = body1_input.to_vec();
-    expected_body2.push(expected_model_switch_msg);
+    expected_body2.push(expected_settings_update_msg);
     expected_body2.push(expected_env_msg_2);
-    expected_body2.push(expected_permissions_msg_2);
     expected_body2.push(expected_user_message_2);
     assert_eq!(body2["input"], serde_json::Value::Array(expected_body2));
 
@@ -746,7 +761,7 @@ async fn send_user_turn_with_no_changes_does_not_send_environment_context() -> a
             sandbox_policy: default_sandbox_policy.clone(),
             model: default_model.clone(),
             effort: default_effort,
-            summary: default_summary,
+            summary: default_summary.unwrap_or(ReasoningSummary::Auto),
             collaboration_mode: None,
             final_output_json_schema: None,
             personality: None,
@@ -765,7 +780,7 @@ async fn send_user_turn_with_no_changes_does_not_send_environment_context() -> a
             sandbox_policy: default_sandbox_policy.clone(),
             model: default_model.clone(),
             effort: default_effort,
-            summary: default_summary,
+            summary: default_summary.unwrap_or(ReasoningSummary::Auto),
             collaboration_mode: None,
             final_output_json_schema: None,
             personality: None,
@@ -773,8 +788,10 @@ async fn send_user_turn_with_no_changes_does_not_send_environment_context() -> a
         .await?;
     wait_for_event(&codex, |ev| matches!(ev, EventMsg::TurnComplete(_))).await;
 
-    let body1 = req1.single_request().body_json();
-    let body2 = req2.single_request().body_json();
+    let request1 = req1.single_request();
+    let request2 = req2.single_request();
+    let body1 = request1.body_json();
+    let body2 = request2.body_json();
 
     let expected_permissions_msg = body1["input"][0].clone();
     let expected_ui_msg = body1["input"][1].clone();
@@ -782,13 +799,18 @@ async fn send_user_turn_with_no_changes_does_not_send_environment_context() -> a
     let shell = default_user_shell();
     let default_cwd_lossy = default_cwd.to_string_lossy();
 
-    let expected_env_msg_1 = text_user_input(default_env_context_str(&default_cwd_lossy, &shell));
+    let expected_contextual_user_msg_1 = text_user_input_parts(vec![
+        expected_ui_msg["content"][0]["text"]
+            .as_str()
+            .expect("cached user instructions text")
+            .to_string(),
+        default_env_context_str(&default_cwd_lossy, &shell),
+    ]);
     let expected_user_message_1 = text_user_input("hello 1".to_string());
 
     let expected_input_1 = serde_json::Value::Array(vec![
         expected_permissions_msg.clone(),
-        expected_ui_msg.clone(),
-        expected_env_msg_1.clone(),
+        expected_contextual_user_msg_1.clone(),
         expected_user_message_1.clone(),
     ]);
     assert_eq!(body1["input"], expected_input_1);
@@ -796,8 +818,7 @@ async fn send_user_turn_with_no_changes_does_not_send_environment_context() -> a
     let expected_user_message_2 = text_user_input("hello 2".to_string());
     let expected_input_2 = serde_json::Value::Array(vec![
         expected_permissions_msg,
-        expected_ui_msg,
-        expected_env_msg_1,
+        expected_contextual_user_msg_1,
         expected_user_message_1,
         expected_user_message_2,
     ]);
@@ -854,7 +875,7 @@ async fn send_user_turn_with_changes_sends_environment_context() -> anyhow::Resu
             sandbox_policy: default_sandbox_policy.clone(),
             model: default_model,
             effort: default_effort,
-            summary: default_summary,
+            summary: default_summary.unwrap_or(ReasoningSummary::Auto),
             collaboration_mode: None,
             final_output_json_schema: None,
             personality: None,
@@ -881,49 +902,53 @@ async fn send_user_turn_with_changes_sends_environment_context() -> anyhow::Resu
         .await?;
     wait_for_event(&codex, |ev| matches!(ev, EventMsg::TurnComplete(_))).await;
 
-    let body1 = req1.single_request().body_json();
-    let body2 = req2.single_request().body_json();
+    let request1 = req1.single_request();
+    let request2 = req2.single_request();
+    let body1 = request1.body_json();
+    let body2 = request2.body_json();
 
     let expected_permissions_msg = body1["input"][0].clone();
     let expected_ui_msg = body1["input"][1].clone();
 
     let shell = default_user_shell();
     let expected_env_text_1 = default_env_context_str(&default_cwd.to_string_lossy(), &shell);
-    let expected_env_msg_1 = text_user_input(expected_env_text_1);
+    let expected_contextual_user_msg_1 = text_user_input_parts(vec![
+        expected_ui_msg["content"][0]["text"]
+            .as_str()
+            .expect("cached user instructions text")
+            .to_string(),
+        expected_env_text_1,
+    ]);
     let expected_user_message_1 = text_user_input("hello 1".to_string());
     let expected_input_1 = serde_json::Value::Array(vec![
         expected_permissions_msg.clone(),
-        expected_ui_msg.clone(),
-        expected_env_msg_1.clone(),
+        expected_contextual_user_msg_1.clone(),
         expected_user_message_1.clone(),
     ]);
     assert_eq!(body1["input"], expected_input_1);
 
     let body1_input = body1["input"].as_array().expect("input array");
-    let expected_model_switch_msg = body2["input"][body1_input.len()].clone();
+    let expected_settings_update_msg = body2["input"][body1_input.len()].clone();
+    assert_ne!(
+        expected_settings_update_msg, expected_permissions_msg,
+        "expected updated permissions message after policy change"
+    );
     assert_eq!(
-        expected_model_switch_msg["role"].as_str(),
+        expected_settings_update_msg["role"].as_str(),
         Some("developer")
     );
     assert!(
-        expected_model_switch_msg["content"][0]["text"]
-            .as_str()
-            .is_some_and(|text| text.contains("<model_switch>")),
-        "expected model switch message after model override: {expected_model_switch_msg:?}"
-    );
-    let expected_permissions_msg_2 = body2["input"][body1_input.len() + 1].clone();
-    assert_ne!(
-        expected_permissions_msg_2, expected_permissions_msg,
-        "expected updated permissions message after policy change"
+        request2.has_message_with_input_texts("developer", |texts| {
+            texts.iter().any(|text| text.contains("<model_switch>"))
+        }),
+        "expected model switch section after model override: {expected_settings_update_msg:?}"
     );
     let expected_user_message_2 = text_user_input("hello 2".to_string());
     let expected_input_2 = serde_json::Value::Array(vec![
         expected_permissions_msg,
-        expected_ui_msg,
-        expected_env_msg_1,
+        expected_contextual_user_msg_1,
         expected_user_message_1,
-        expected_model_switch_msg,
-        expected_permissions_msg_2,
+        expected_settings_update_msg,
         expected_user_message_2,
     ]);
     assert_eq!(body2["input"], expected_input_2);

codex-rs/core/tests/suite/remote_models.rs

@@ -175,7 +175,9 @@ async fn remote_models_long_model_slug_is_sent_with_high_reasoning() -> Result<(
             sandbox_policy: config.permissions.sandbox_policy.get().clone(),
             model: requested_model.to_string(),
             effort: None,
-            summary: config.model_reasoning_summary,
+            summary: config
+                .model_reasoning_summary
+                .unwrap_or(ReasoningSummary::Auto),
             collaboration_mode: None,
             personality: None,
         })
@@ -227,7 +229,9 @@ async fn namespaced_model_slug_uses_catalog_metadata_without_fallback_warning()
             sandbox_policy: config.permissions.sandbox_policy.get().clone(),
             model: requested_model.to_string(),
             effort: None,
-            summary: config.model_reasoning_summary,
+            summary: config
+                .model_reasoning_summary
+                .unwrap_or(ReasoningSummary::Auto),
             collaboration_mode: None,
             personality: None,
         })
@@ -284,6 +288,7 @@ async fn remote_models_remote_model_uses_unified_exec() -> Result<()> {
         base_instructions: "base instructions".to_string(),
         model_messages: None,
         supports_reasoning_summaries: false,
+        default_reasoning_summary: ReasoningSummary::Auto,
         support_verbosity: false,
         default_verbosity: None,
         apply_patch_tool_type: None,
@@ -520,6 +525,7 @@ async fn remote_models_apply_remote_base_instructions() -> Result<()> {
         base_instructions: remote_base.to_string(),
         model_messages: None,
         supports_reasoning_summaries: false,
+        default_reasoning_summary: ReasoningSummary::Auto,
         support_verbosity: false,
         default_verbosity: None,
         apply_patch_tool_type: None,
@@ -980,6 +986,7 @@ fn test_remote_model_with_policy(
         base_instructions: "base instructions".to_string(),
         model_messages: None,
         supports_reasoning_summaries: false,
+        default_reasoning_summary: ReasoningSummary::Auto,
         support_verbosity: false,
         default_verbosity: None,
         apply_patch_tool_type: None,

codex-rs/core/tests/suite/resume_warning.rs

@@ -4,6 +4,7 @@ use codex_core::CodexAuth;
 use codex_core::NewThread;
 use codex_protocol::ThreadId;
 use codex_protocol::config_types::ModeKind;
+use codex_protocol::config_types::ReasoningSummary;
 use codex_protocol::protocol::EventMsg;
 use codex_protocol::protocol::InitialHistory;
 use codex_protocol::protocol::ResumedHistory;
@@ -34,7 +35,9 @@ fn resume_history(
         personality: None,
         collaboration_mode: None,
         effort: config.model_reasoning_effort,
-        summary: config.model_reasoning_summary,
+        summary: config
+            .model_reasoning_summary
+            .unwrap_or(ReasoningSummary::Auto),
         user_instructions: None,
         developer_instructions: None,
         final_output_json_schema: None,

codex-rs/core/tests/suite/review.rs

@@ -605,7 +605,9 @@ async fn review_input_isolated_from_parent_history() {
 
     let env_text = input
         .iter()
-        .filter_map(|msg| msg["content"][0]["text"].as_str())
+        .filter_map(|msg| msg.get("content").and_then(|content| content.as_array()))
+        .flat_map(|content| content.iter())
+        .filter_map(|entry| entry.get("text").and_then(|text| text.as_str()))
         .find(|text| text.starts_with(ENVIRONMENT_CONTEXT_OPEN_TAG))
         .expect("env text");
     assert!(
@@ -615,7 +617,9 @@ async fn review_input_isolated_from_parent_history() {
 
     let review_text = input
         .iter()
-        .filter_map(|msg| msg["content"][0]["text"].as_str())
+        .filter_map(|msg| msg.get("content").and_then(|content| content.as_array()))
+        .flat_map(|content| content.iter())
+        .filter_map(|entry| entry.get("text").and_then(|text| text.as_str()))
         .find(|text| *text == review_prompt)
         .expect("review prompt text");
     assert_eq!(

codex-rs/core/tests/suite/rmcp_client.rs

@@ -398,6 +398,7 @@ async fn stdio_image_responses_are_sanitized_for_text_only_model() -> anyhow::Re
                 base_instructions: "base instructions".to_string(),
                 model_messages: None,
                 supports_reasoning_summaries: false,
+                default_reasoning_summary: ReasoningSummary::Auto,
                 support_verbosity: false,
                 default_verbosity: None,
                 apply_patch_tool_type: None,

codex-rs/core/tests/suite/snapshots/all__suite__compact__manual_compact_with_history_shapes.snap

@@ -6,16 +6,18 @@ Scenario: Manual /compact with prior user history compacts existing history and
 
 ## Local Compaction Request
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:first manual turn
-04:message/assistant:FIRST_REPLY
-05:message/user:<SUMMARIZATION_PROMPT>
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:first manual turn
+03:message/assistant:FIRST_REPLY
+04:message/user:<SUMMARIZATION_PROMPT>
 
 ## Local Post-Compaction History Layout
 00:message/user:first manual turn
 01:message/user:<COMPACTION_SUMMARY>\nFIRST_MANUAL_SUMMARY
 02:message/developer:<PERMISSIONS_INSTRUCTIONS>
-03:message/user:<AGENTS_MD>
-04:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-05:message/user:second manual turn
+03:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+04:message/user:second manual turn

codex-rs/core/tests/suite/snapshots/all__suite__compact__manual_compact_without_prev_user_shapes.snap

@@ -6,13 +6,15 @@ Scenario: Manual /compact with no prior user turn currently still issues a compa
 
 ## Local Compaction Request
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:<SUMMARIZATION_PROMPT>
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:<SUMMARIZATION_PROMPT>
 
 ## Local Post-Compaction History Layout
 00:message/user:<COMPACTION_SUMMARY>\nMANUAL_EMPTY_SUMMARY
 01:message/developer:<PERMISSIONS_INSTRUCTIONS>
-02:message/user:<AGENTS_MD>
-03:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-04:message/user:AFTER_MANUAL_EMPTY_COMPACT
+02:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+03:message/user:AFTER_MANUAL_EMPTY_COMPACT

codex-rs/core/tests/suite/snapshots/all__suite__compact__mid_turn_compaction_shapes.snap

@@ -1,22 +1,23 @@
 ---
 source: core/tests/suite/compact.rs
-assertion_line: 2646
 expression: "format_labeled_requests_snapshot(\"True mid-turn continuation compaction after tool output: compact request includes tool artifacts, and the continuation request includes the summary in the same turn.\",\n&[(\"Local Compaction Request\", &auto_compact_mock.single_request()),\n(\"Local Post-Compaction History Layout\",\n&post_auto_compact_mock.single_request()),])"
 ---
 Scenario: True mid-turn continuation compaction after tool output: compact request includes tool artifacts, and the continuation request includes the summary in the same turn.
 
 ## Local Compaction Request
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:function call limit push
-04:function_call/test_tool
-05:function_call_output:unsupported call: test_tool
-06:message/user:<SUMMARIZATION_PROMPT>
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:function call limit push
+03:function_call/test_tool
+04:function_call_output:unsupported call: test_tool
+05:message/user:<SUMMARIZATION_PROMPT>
 
 ## Local Post-Compaction History Layout
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:function call limit push
-04:message/user:<COMPACTION_SUMMARY>\nAUTO_SUMMARY
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:function call limit push
+03:message/user:<COMPACTION_SUMMARY>\nAUTO_SUMMARY

codex-rs/core/tests/suite/snapshots/all__suite__compact__pre_sampling_model_switch_compaction_shapes.snap

@@ -1,30 +1,35 @@
 ---
 source: core/tests/suite/compact.rs
+assertion_line: 1791
 expression: "format_labeled_requests_snapshot(\"Pre-sampling compaction on model switch to a smaller context window: current behavior compacts using prior-turn history only (incoming user message excluded), and the follow-up request carries compacted history plus the new user message.\",\n&[(\"Initial Request (Previous Model)\", &requests[0]),\n(\"Pre-sampling Compaction Request\", &requests[1]),\n(\"Post-Compaction Follow-up Request (Next Model)\", &requests[2]),])"
 ---
 Scenario: Pre-sampling compaction on model switch to a smaller context window: current behavior compacts using prior-turn history only (incoming user message excluded), and the follow-up request carries compacted history plus the new user message.
 
 ## Initial Request (Previous Model)
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/developer:<PERMISSIONS_INSTRUCTIONS>
-04:message/user:before switch
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/developer:<PERMISSIONS_INSTRUCTIONS>
+03:message/user:before switch
 
 ## Pre-sampling Compaction Request
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/developer:<PERMISSIONS_INSTRUCTIONS>
-04:message/user:before switch
-05:message/assistant:before switch
-06:message/user:<SUMMARIZATION_PROMPT>
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/developer:<PERMISSIONS_INSTRUCTIONS>
+03:message/user:before switch
+04:message/assistant:before switch
+05:message/user:<SUMMARIZATION_PROMPT>
 
 ## Post-Compaction Follow-up Request (Next Model)
 00:message/user:before switch
 01:message/user:<COMPACTION_SUMMARY>\nPRE_SAMPLING_SUMMARY
-02:message/developer:<model_switch>\nThe user was previously using a different model....
-03:message/developer:<PERMISSIONS_INSTRUCTIONS>
-04:message/user:<AGENTS_MD>
-05:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-06:message/user:after switch
+02:message/developer[2]:
+    [01] <model_switch>\nThe user was previously using a different model....
+    [02] <PERMISSIONS_INSTRUCTIONS>
+03:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+04:message/user:after switch

codex-rs/core/tests/suite/snapshots/all__suite__compact__pre_turn_compaction_context_window_exceeded_shapes.snap

@@ -6,8 +6,9 @@ Scenario: Pre-turn auto-compaction context-window failure: compaction request ex
 
 ## Local Compaction Request (Incoming User Excluded)
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:USER_ONE
-04:message/assistant:FIRST_REPLY
-05:message/user:<SUMMARIZATION_PROMPT>
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:USER_ONE
+03:message/assistant:FIRST_REPLY
+04:message/user:<SUMMARIZATION_PROMPT>

codex-rs/core/tests/suite/snapshots/all__suite__compact__pre_turn_compaction_including_incoming_shapes.snap

@@ -6,19 +6,25 @@ Scenario: Pre-turn auto-compaction with a context override emits the context dif
 
 ## Local Compaction Request
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:USER_ONE
-04:message/assistant:FIRST_REPLY
-05:message/user:USER_TWO
-06:message/assistant:SECOND_REPLY
-07:message/user:<SUMMARIZATION_PROMPT>
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:USER_ONE
+03:message/assistant:FIRST_REPLY
+04:message/user:USER_TWO
+05:message/assistant:SECOND_REPLY
+06:message/user:<SUMMARIZATION_PROMPT>
 
 ## Local Post-Compaction History Layout
 00:message/user:USER_ONE
 01:message/user:USER_TWO
 02:message/user:<COMPACTION_SUMMARY>\nPRE_TURN_SUMMARY
 03:message/developer:<PERMISSIONS_INSTRUCTIONS>
-04:message/user:<AGENTS_MD>
-05:message/user:<ENVIRONMENT_CONTEXT:cwd=PRETURN_CONTEXT_DIFF_CWD>
-06:message/user:<image> | <input_image:image_url> | </image> | USER_THREE
+04:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=PRETURN_CONTEXT_DIFF_CWD>
+05:message/user[4]:
+    [01] <image>
+    [02] <input_image:image_url>
+    [03] </image>
+    [04] USER_THREE

codex-rs/core/tests/suite/snapshots/all__suite__compact__pre_turn_compaction_strips_incoming_model_switch_shapes.snap

@@ -1,31 +1,36 @@
 ---
 source: core/tests/suite/compact.rs
+assertion_line: 3188
 expression: "format_labeled_requests_snapshot(\"Pre-turn compaction during model switch (without pre-sampling model-switch compaction): current behavior strips incoming <model_switch> from the compact request and restores it in the post-compaction follow-up request.\",\n&[(\"Initial Request (Previous Model)\", &requests[0]),\n(\"Local Compaction Request\", &requests[1]),\n(\"Local Post-Compaction History Layout\", &requests[2]),])"
 ---
 Scenario: Pre-turn compaction during model switch (without pre-sampling model-switch compaction): current behavior strips incoming <model_switch> from the compact request and restores it in the post-compaction follow-up request.
 
 ## Initial Request (Previous Model)
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/developer:<PERMISSIONS_INSTRUCTIONS>
-04:message/user:BEFORE_SWITCH_USER
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/developer:<PERMISSIONS_INSTRUCTIONS>
+03:message/user:BEFORE_SWITCH_USER
 
 ## Local Compaction Request
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/developer:<PERMISSIONS_INSTRUCTIONS>
-04:message/user:BEFORE_SWITCH_USER
-05:message/assistant:BEFORE_SWITCH_REPLY
-06:message/user:<SUMMARIZATION_PROMPT>
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/developer:<PERMISSIONS_INSTRUCTIONS>
+03:message/user:BEFORE_SWITCH_USER
+04:message/assistant:BEFORE_SWITCH_REPLY
+05:message/user:<SUMMARIZATION_PROMPT>
 
 ## Local Post-Compaction History Layout
 00:message/user:BEFORE_SWITCH_USER
 01:message/user:<COMPACTION_SUMMARY>\nPRETURN_SWITCH_SUMMARY
-02:message/developer:<model_switch>\nThe user was previously using a different model....
-03:message/developer:<PERMISSIONS_INSTRUCTIONS>
-04:message/developer:<personality_spec> The user has requested a new communication st...
-05:message/user:<AGENTS_MD>
-06:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-07:message/user:AFTER_SWITCH_USER
+02:message/developer[3]:
+    [01] <model_switch>\nThe user was previously using a different model....
+    [02] <PERMISSIONS_INSTRUCTIONS>
+    [03] <personality_spec> The user has requested a new communication st...
+03:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+04:message/user:AFTER_SWITCH_USER

codex-rs/core/tests/suite/snapshots/all__suite__compact_remote__remote_manual_compact_with_history_shapes.snap

@@ -6,14 +6,16 @@ Scenario: Remote manual /compact where remote compact output is compaction-only:
 
 ## Remote Compaction Request
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:hello remote compact
-04:message/assistant:FIRST_REMOTE_REPLY
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:hello remote compact
+03:message/assistant:FIRST_REMOTE_REPLY
 
 ## Remote Post-Compaction History Layout
 00:compaction:encrypted=true
 01:message/developer:<PERMISSIONS_INSTRUCTIONS>
-02:message/user:<AGENTS_MD>
-03:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-04:message/user:after compact
+02:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+03:message/user:after compact

codex-rs/core/tests/suite/snapshots/all__suite__compact_remote__remote_manual_compact_without_prev_user_shapes.snap

@@ -6,11 +6,13 @@ Scenario: Remote manual /compact with no prior user turn still issues a compact
 
 ## Remote Compaction Request
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
 
 ## Remote Post-Compaction History Layout
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:USER_ONE
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:USER_ONE

codex-rs/core/tests/suite/snapshots/all__suite__compact_remote__remote_mid_turn_compaction_multi_summary_reinjects_above_last_summary_shapes.snap

@@ -1,6 +1,5 @@
 ---
 source: core/tests/suite/compact_remote.rs
-assertion_line: 1876
 expression: "format_labeled_requests_snapshot(\"After a prior manual /compact produced an older remote compaction item, the next turn hits remote auto-compaction before the next sampling request. The compact request carries forward that earlier compaction item, and the next sampling request shows the latest compaction item with context reinjected before USER_TWO.\",\n&[(\"Remote Compaction Request\", &compact_request),\n(\"Second Turn Request (After Compaction)\", &second_turn_request),])"
 ---
 Scenario: After a prior manual /compact produced an older remote compaction item, the next turn hits remote auto-compaction before the next sampling request. The compact request carries forward that earlier compaction item, and the next sampling request shows the latest compaction item with context reinjected before USER_TWO.
@@ -13,6 +12,7 @@ Scenario: After a prior manual /compact produced an older remote compaction item
 00:message/user:USER_ONE
 01:compaction:encrypted=true
 02:message/developer:<PERMISSIONS_INSTRUCTIONS>
-03:message/user:<AGENTS_MD>
-04:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-05:message/user:USER_TWO
+03:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+04:message/user:USER_TWO

codex-rs/core/tests/suite/snapshots/all__suite__compact_remote__remote_mid_turn_compaction_shapes.snap

@@ -6,15 +6,17 @@ Scenario: Remote mid-turn continuation compaction after tool output: compact req
 
 ## Remote Compaction Request
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:USER_ONE
-04:function_call/test_tool
-05:function_call_output:unsupported call: test_tool
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:USER_ONE
+03:function_call/test_tool
+04:function_call_output:unsupported call: test_tool
 
 ## Remote Post-Compaction History Layout
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:USER_ONE
-04:compaction:encrypted=true
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:USER_ONE
+03:compaction:encrypted=true

codex-rs/core/tests/suite/snapshots/all__suite__compact_remote__remote_mid_turn_compaction_summary_only_reinjects_context_shapes.snap

@@ -1,19 +1,21 @@
 ---
 source: core/tests/suite/compact_remote.rs
-expression: "format_labeled_requests_snapshot(\"Remote mid-turn compaction where compact output has only a compaction item: continuation layout reinjects context before that compaction item.\",\n&[(\"Remote Compaction Request\", &compact_request),\n(\"Remote Post-Compaction History Layout\", &requests[1]),])"
+expression: "format_labeled_requests_snapshot(\"Remote mid-turn compaction where compact output has only a compaction item: continuation layout reinjects context before that compaction item.\",\n&[(\"Remote Compaction Request\", &compact_request),\n(\"Remote Post-Compaction History Layout\", &post_compact_turn_request),])"
 ---
 Scenario: Remote mid-turn compaction where compact output has only a compaction item: continuation layout reinjects context before that compaction item.
 
 ## Remote Compaction Request
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:USER_ONE
-04:function_call/test_tool
-05:function_call_output:unsupported call: test_tool
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:USER_ONE
+03:function_call/test_tool
+04:function_call_output:unsupported call: test_tool
 
 ## Remote Post-Compaction History Layout
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:compaction:encrypted=true
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:compaction:encrypted=true

codex-rs/core/tests/suite/snapshots/all__suite__compact_remote__remote_pre_turn_compaction_context_window_exceeded_shapes.snap

@@ -6,7 +6,8 @@ Scenario: Remote pre-turn auto-compaction context-window failure: compaction req
 
 ## Remote Compaction Request (Incoming User Excluded)
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:USER_ONE
-04:message/assistant:REMOTE_FIRST_REPLY
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:USER_ONE
+03:message/assistant:REMOTE_FIRST_REPLY

codex-rs/core/tests/suite/snapshots/all__suite__compact_remote__remote_pre_turn_compaction_failure_shapes.snap

@@ -6,7 +6,8 @@ Scenario: Remote pre-turn auto-compaction parse failure: compaction request excl
 
 ## Remote Compaction Request (Incoming User Excluded)
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:turn that exceeds token threshold
-04:message/assistant:initial turn complete
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:turn that exceeds token threshold
+03:message/assistant:initial turn complete

codex-rs/core/tests/suite/snapshots/all__suite__compact_remote__remote_pre_turn_compaction_including_incoming_shapes.snap

@@ -6,18 +6,20 @@ Scenario: Remote pre-turn auto-compaction with a context override emits the cont
 
 ## Remote Compaction Request
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:USER_ONE
-04:message/assistant:REMOTE_FIRST_REPLY
-05:message/user:USER_TWO
-06:message/assistant:REMOTE_SECOND_REPLY
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:USER_ONE
+03:message/assistant:REMOTE_FIRST_REPLY
+04:message/user:USER_TWO
+05:message/assistant:REMOTE_SECOND_REPLY
 
 ## Remote Post-Compaction History Layout
 00:message/user:USER_ONE
 01:message/user:USER_TWO
 02:compaction:encrypted=true
 03:message/developer:<PERMISSIONS_INSTRUCTIONS>
-04:message/user:<AGENTS_MD>
-05:message/user:<ENVIRONMENT_CONTEXT:cwd=PRETURN_CONTEXT_DIFF_CWD>
-06:message/user:USER_THREE
+04:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=PRETURN_CONTEXT_DIFF_CWD>
+05:message/user:USER_THREE

codex-rs/core/tests/suite/snapshots/all__suite__compact_remote__remote_pre_turn_compaction_strips_incoming_model_switch_shapes.snap

@@ -1,28 +1,33 @@
 ---
 source: core/tests/suite/compact_remote.rs
+assertion_line: 1514
 expression: "format_labeled_requests_snapshot(\"Remote pre-turn compaction during model switch currently excludes incoming user input, strips incoming <model_switch> from the compact request payload, and restores it in the post-compaction follow-up request.\",\n&[(\"Initial Request (Previous Model)\", &initial_turn_request),\n(\"Remote Compaction Request\", &compact_request),\n(\"Remote Post-Compaction History Layout\", &post_compact_turn_request),])"
 ---
 Scenario: Remote pre-turn compaction during model switch currently excludes incoming user input, strips incoming <model_switch> from the compact request payload, and restores it in the post-compaction follow-up request.
 
 ## Initial Request (Previous Model)
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:BEFORE_SWITCH_USER
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:BEFORE_SWITCH_USER
 
 ## Remote Compaction Request
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:BEFORE_SWITCH_USER
-04:message/assistant:BEFORE_SWITCH_REPLY
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:BEFORE_SWITCH_USER
+03:message/assistant:BEFORE_SWITCH_REPLY
 
 ## Remote Post-Compaction History Layout
 00:message/user:BEFORE_SWITCH_USER
 01:compaction:encrypted=true
-02:message/developer:<model_switch>\nThe user was previously using a different model....
-03:message/developer:<PERMISSIONS_INSTRUCTIONS>
-04:message/developer:<personality_spec> The user has requested a new communication st...
-05:message/user:<AGENTS_MD>
-06:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-07:message/user:AFTER_SWITCH_USER
+02:message/developer[3]:
+    [01] <model_switch>\nThe user was previously using a different model....
+    [02] <PERMISSIONS_INSTRUCTIONS>
+    [03] <personality_spec> The user has requested a new communication st...
+03:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+04:message/user:AFTER_SWITCH_USER

codex-rs/core/tests/suite/snapshots/all__suite__model_visible_layout__model_visible_layout_cwd_change_does_not_refresh_agents.snap

@@ -6,19 +6,21 @@ Scenario: Second turn changes cwd to a directory with different AGENTS.md; curre
 
 ## First Request (agents_one)
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/developer:<PERMISSIONS_INSTRUCTIONS>
 03:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-04:message/developer:<PERMISSIONS_INSTRUCTIONS>
-05:message/user:first turn in agents_one
+04:message/user:first turn in agents_one
 
 ## Second Request (agents_two cwd)
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/developer:<PERMISSIONS_INSTRUCTIONS>
 03:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-04:message/developer:<PERMISSIONS_INSTRUCTIONS>
-05:message/user:first turn in agents_one
-06:message/assistant:turn one complete
-07:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-08:message/user:second turn in agents_two
+04:message/user:first turn in agents_one
+05:message/assistant:turn one complete
+06:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
+07:message/user:second turn in agents_two

codex-rs/core/tests/suite/snapshots/all__suite__model_visible_layout__model_visible_layout_environment_context_includes_one_subagent.snap

@@ -0,0 +1,6 @@
+---
+source: core/tests/suite/model_visible_layout.rs
+assertion_line: 476
+expression: "format_environment_context_subagents_snapshot(&[\"- agent-1: Atlas\"])"
+---
+00:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>:subagents=1>

codex-rs/core/tests/suite/snapshots/all__suite__model_visible_layout__model_visible_layout_environment_context_includes_two_subagents.snap

@@ -0,0 +1,6 @@
+---
+source: core/tests/suite/model_visible_layout.rs
+assertion_line: 486
+expression: "format_environment_context_subagents_snapshot(&[\"- agent-1: Atlas\",\n\"- agent-2: Juniper\",])"
+---
+00:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>:subagents=2>

codex-rs/core/tests/suite/snapshots/all__suite__model_visible_layout__model_visible_layout_resume_override_matches_rollout_model.snap

@@ -1,21 +1,22 @@
 ---
 source: core/tests/suite/model_visible_layout.rs
-assertion_line: 435
 expression: "format_labeled_requests_snapshot(\"First post-resume turn where pre-turn override sets model to rollout model; no model-switch update should appear.\",\n&[(\"Last Request Before Resume\", &initial_request),\n(\"First Request After Resume + Override\", &resumed_request),])"
 ---
 Scenario: First post-resume turn where pre-turn override sets model to rollout model; no model-switch update should appear.
 
 ## Last Request Before Resume
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:seed resume history
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:seed resume history
 
 ## First Request After Resume + Override
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:seed resume history
-04:message/assistant:recorded before resume
-05:message/user:<ENVIRONMENT_CONTEXT:cwd=PRETURN_CONTEXT_DIFF_CWD>
-06:message/user:first resumed turn after model override
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:seed resume history
+03:message/assistant:recorded before resume
+04:message/user:<ENVIRONMENT_CONTEXT:cwd=PRETURN_CONTEXT_DIFF_CWD>
+05:message/user:first resumed turn after model override

codex-rs/core/tests/suite/snapshots/all__suite__model_visible_layout__model_visible_layout_resume_with_personality_change.snap

@@ -1,23 +1,25 @@
 ---
 source: core/tests/suite/model_visible_layout.rs
-assertion_line: 337
 expression: "format_labeled_requests_snapshot(\"First post-resume turn where resumed config model differs from rollout and personality changes.\",\n&[(\"Last Request Before Resume\", &initial_request),\n(\"First Request After Resume\", &resumed_request),])"
 ---
 Scenario: First post-resume turn where resumed config model differs from rollout and personality changes.
 
 ## Last Request Before Resume
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:seed resume history
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:seed resume history
 
 ## First Request After Resume
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/user:seed resume history
-04:message/assistant:recorded before resume
-05:message/developer:<model_switch>\nThe user was previously using a different model. Please continue the conversatio...
-06:message/user:<ENVIRONMENT_CONTEXT:cwd=PRETURN_CONTEXT_DIFF_CWD>
-07:message/developer:<PERMISSIONS_INSTRUCTIONS>
-08:message/user:resume and change personality
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/user:seed resume history
+03:message/assistant:recorded before resume
+04:message/developer[2]:
+    [01] <model_switch>\nThe user was previously using a different model. Please continue the conversatio...
+    [02] <PERMISSIONS_INSTRUCTIONS>
+05:message/user:<ENVIRONMENT_CONTEXT:cwd=PRETURN_CONTEXT_DIFF_CWD>
+06:message/user:resume and change personality

codex-rs/core/tests/suite/snapshots/all__suite__model_visible_layout__model_visible_layout_turn_overrides.snap

@@ -6,19 +6,22 @@ Scenario: Second turn changes cwd, approval policy, and personality while keepin
 
 ## First Request (Baseline)
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/developer:<PERMISSIONS_INSTRUCTIONS>
-04:message/user:first turn
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/developer:<PERMISSIONS_INSTRUCTIONS>
+03:message/user:first turn
 
 ## Second Request (Turn Overrides)
 00:message/developer:<PERMISSIONS_INSTRUCTIONS>
-01:message/user:<AGENTS_MD>
-02:message/user:<ENVIRONMENT_CONTEXT:cwd=<CWD>>
-03:message/developer:<PERMISSIONS_INSTRUCTIONS>
-04:message/user:first turn
-05:message/assistant:turn one complete
+01:message/user[2]:
+    [01] <AGENTS_MD>
+    [02] <ENVIRONMENT_CONTEXT:cwd=<CWD>>
+02:message/developer:<PERMISSIONS_INSTRUCTIONS>
+03:message/user:first turn
+04:message/assistant:turn one complete
+05:message/developer[2]:
+    [01] <PERMISSIONS_INSTRUCTIONS>
+    [02] <personality_spec> The user has requested a new communication style. Future messages should adhe...
 06:message/user:<ENVIRONMENT_CONTEXT:cwd=PRETURN_CONTEXT_DIFF_CWD>
-07:message/developer:<PERMISSIONS_INSTRUCTIONS>
-08:message/developer:<personality_spec> The user has requested a new communication style. Future messages should adhe...
-09:message/user:second turn with context updates
+07:message/user:second turn with context updates

codex-rs/core/tests/suite/subagent_notifications.rs

@@ -20,6 +20,8 @@ use tokio::time::sleep;
 use wiremock::MockServer;
 
 const SPAWN_CALL_ID: &str = "spawn-call-1";
+const FORKED_SPAWN_AGENT_OUTPUT_MESSAGE: &str = "You are the newly spawned agent. The prior conversation history was forked from your parent agent. Treat the next user message as your new task, and use the forked history only as background context.";
+const TURN_0_FORK_PROMPT: &str = "seed fork context";
 const TURN_1_PROMPT: &str = "spawn a child and continue";
 const TURN_2_NO_WAIT_PROMPT: &str = "follow up without wait";
 const CHILD_PROMPT: &str = "child: do work";
@@ -194,3 +196,116 @@ async fn subagent_notification_is_included_without_wait() -> Result<()> {
 
     Ok(())
 }
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn spawned_child_receives_forked_parent_context() -> Result<()> {
+    skip_if_no_network!(Ok(()));
+
+    let server = start_mock_server().await;
+
+    let seed_turn = mount_sse_once_match(
+        &server,
+        |req: &wiremock::Request| body_contains(req, TURN_0_FORK_PROMPT),
+        sse(vec![
+            ev_response_created("resp-seed-1"),
+            ev_assistant_message("msg-seed-1", "seeded"),
+            ev_completed("resp-seed-1"),
+        ]),
+    )
+    .await;
+
+    let spawn_args = serde_json::to_string(&json!({
+        "message": CHILD_PROMPT,
+        "fork_context": true,
+    }))?;
+    let spawn_turn = mount_sse_once_match(
+        &server,
+        |req: &wiremock::Request| body_contains(req, TURN_1_PROMPT),
+        sse(vec![
+            ev_response_created("resp-turn1-1"),
+            ev_function_call(SPAWN_CALL_ID, "spawn_agent", &spawn_args),
+            ev_completed("resp-turn1-1"),
+        ]),
+    )
+    .await;
+
+    let _child_request_log = mount_sse_once_match(
+        &server,
+        |req: &wiremock::Request| body_contains(req, CHILD_PROMPT),
+        sse(vec![
+            ev_response_created("resp-child-1"),
+            ev_assistant_message("msg-child-1", "child done"),
+            ev_completed("resp-child-1"),
+        ]),
+    )
+    .await;
+
+    let _turn1_followup = mount_sse_once_match(
+        &server,
+        |req: &wiremock::Request| body_contains(req, SPAWN_CALL_ID),
+        sse(vec![
+            ev_response_created("resp-turn1-2"),
+            ev_assistant_message("msg-turn1-2", "parent done"),
+            ev_completed("resp-turn1-2"),
+        ]),
+    )
+    .await;
+
+    let mut builder = test_codex().with_config(|config| {
+        config.features.enable(Feature::Collab);
+    });
+    let test = builder.build(&server).await?;
+
+    test.submit_turn(TURN_0_FORK_PROMPT).await?;
+    let _ = seed_turn.single_request();
+
+    test.submit_turn(TURN_1_PROMPT).await?;
+    let _ = spawn_turn.single_request();
+
+    let deadline = Instant::now() + Duration::from_secs(2);
+    let child_request = loop {
+        if let Some(request) = server
+            .received_requests()
+            .await
+            .unwrap_or_default()
+            .into_iter()
+            .find(|request| {
+                body_contains(request, CHILD_PROMPT)
+                    && body_contains(request, FORKED_SPAWN_AGENT_OUTPUT_MESSAGE)
+            })
+        {
+            break request;
+        }
+        if Instant::now() >= deadline {
+            anyhow::bail!("timed out waiting for forked child request");
+        }
+        sleep(Duration::from_millis(10)).await;
+    };
+    assert!(body_contains(&child_request, TURN_0_FORK_PROMPT));
+    assert!(body_contains(&child_request, "seeded"));
+
+    let child_body = child_request
+        .body_json::<serde_json::Value>()
+        .expect("forked child request body should be json");
+    let function_call_output = child_body["input"]
+        .as_array()
+        .and_then(|items| {
+            items.iter().find(|item| {
+                item["type"].as_str() == Some("function_call_output")
+                    && item["call_id"].as_str() == Some(SPAWN_CALL_ID)
+            })
+        })
+        .unwrap_or_else(|| panic!("expected forked child request to include spawn_agent output"));
+    let (content, success) = match &function_call_output["output"] {
+        serde_json::Value::String(text) => (Some(text.as_str()), None),
+        serde_json::Value::Object(output) => (
+            output.get("content").and_then(serde_json::Value::as_str),
+            output.get("success").and_then(serde_json::Value::as_bool),
+        ),
+        _ => (None, None),
+    };
+    assert_eq!(content, Some(FORKED_SPAWN_AGENT_OUTPUT_MESSAGE));
+    assert_ne!(success, Some(false));
+
+    Ok(())
+}

codex-rs/core/tests/suite/view_image.rs

@@ -675,6 +675,7 @@ async fn view_image_tool_returns_unsupported_message_for_text_only_model() -> an
         base_instructions: "base instructions".to_string(),
         model_messages: None,
         supports_reasoning_summaries: false,
+        default_reasoning_summary: ReasoningSummary::Auto,
         support_verbosity: false,
         default_verbosity: None,
         apply_patch_tool_type: None,

codex-rs/exec/src/lib.rs

@@ -560,7 +560,8 @@ pub async fn run_main(cli: Cli, arg0_paths: Arg0DispatchPaths) -> anyhow::Result
                     sandbox_policy: default_sandbox_policy.clone(),
                     model: default_model,
                     effort: default_effort,
-                    summary: default_summary,
+                    summary: default_summary
+                        .unwrap_or(codex_protocol::config_types::ReasoningSummary::Auto),
                     final_output_json_schema: output_schema,
                     collaboration_mode: None,
                     personality: None,

codex-rs/exec/tests/suite/resume.rs

@@ -321,6 +321,9 @@ fn exec_resume_last_respects_cwd_filter_and_all_flag() -> anyhow::Result<()> {
 
     let resumed_path_cwd = find_session_file_containing_marker(&sessions_dir, &marker_a2)
         .expect("no resumed session file containing marker_a2");
+    // The `--all` resume above appends a new turn to `path_b` while running from `dir_a`, so the
+    // session's latest cwd now matches `dir_a`. A subsequent `resume --last` should therefore pick
+    // the newest matching session (`path_b`).
     assert_eq!(
         resumed_path_cwd, path_b,
         "resume --last should prefer sessions whose latest turn context matches the current cwd"

codex-rs/node-version.txt

@@ -1 +1 @@
-24.13.1
+22.22.0

codex-rs/protocol/src/openai_models.rs

@@ -15,6 +15,7 @@ use tracing::warn;
 use ts_rs::TS;
 
 use crate::config_types::Personality;
+use crate::config_types::ReasoningSummary;
 use crate::config_types::Verbosity;
 
 const PERSONALITY_PLACEHOLDER: &str = "{{ personality }}";
@@ -229,6 +230,8 @@ pub struct ModelInfo {
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub model_messages: Option<ModelMessages>,
     pub supports_reasoning_summaries: bool,
+    #[serde(default)]
+    pub default_reasoning_summary: ReasoningSummary,
     pub support_verbosity: bool,
     pub default_verbosity: Option<Verbosity>,
     pub apply_patch_tool_type: Option<ApplyPatchToolType>,
@@ -496,6 +499,7 @@ mod tests {
             base_instructions: "base".to_string(),
             model_messages: spec,
             supports_reasoning_summaries: false,
+            default_reasoning_summary: ReasoningSummary::Auto,
             support_verbosity: false,
             default_verbosity: None,
             apply_patch_tool_type: None,

codex-rs/protocol/src/protocol.rs

@@ -1988,7 +1988,7 @@ impl SessionSource {
                 agent_nickname.clone()
             }
             SessionSource::SubAgent(SubAgentSource::MemoryConsolidation) => {
-                Some("morpheus".to_string())
+                Some("Morpheus".to_string())
             }
             _ => None,
         }

codex-rs/protocol/src/user_input.rs

@@ -3,6 +3,9 @@ use serde::Deserialize;
 use serde::Serialize;
 use ts_rs::TS;
 
+/// Conservative cap so one user message cannot monopolize a large context window.
+pub const MAX_USER_INPUT_TEXT_CHARS: usize = 1 << 20;
+
 /// User input
 #[non_exhaustive]
 #[derive(Debug, Clone, Deserialize, Serialize, PartialEq, TS, JsonSchema)]