From 70e8fe1be3100fd2c1f1942a61f9ac70a0177e91 Mon Sep 17 00:00:00 2001
From: Eric Traut <etraut@openai.com>
Date: Thu, 17 Sep 2026 04:38:18 +0000
Subject: [PATCH] Add opt-in automatic background server startup (#46117)

## What changed

- Add `features.daemon_auto_start`, disabled by default and available through `/experimental`, to start the shared local server for eligible new, resumed, and forked sessions. Changes take effect on the next launch, and disabling the feature persists an explicit `false`.
- Require successful daemon startup and connection when auto-start applies. On failure, show guidance to rerun the same command with `--no-daemon` instead of silently falling back to an embedded server.
- Preserve embedded mode for excluded launches, including Bedrock sign-in, and carry exclusion warnings through resume and fork pickers. Honor `--no-daemon` without an exclusion warning.
- Update `/import` guidance to recommend restarting with `codex --no-daemon`.

## Testing

Add CLI and TUI coverage for automatic daemon attachment, startup and connection failures, `--no-daemon`, picker warning persistence, and Bedrock onboarding with and without a running daemon. Add snapshots and configuration-write assertions for the experimental toggle.

GitOrigin-RevId: 2e8eb163bc7ddd268a86c7546c05a85356c1e9ee
---
 codex-rs/Cargo.lock                           |   2 +
 codex-rs/cli/Cargo.toml                       |   1 +
 codex-rs/cli/tests/daemon_startup.rs          | 217 ++++++++++++++++++
 codex-rs/core/config.schema.json              |   6 +
 codex-rs/features/src/lib.rs                  |  12 +
 codex-rs/tui/Cargo.toml                       |   1 +
 .../src/app/agents_overview_actions_tests.rs  |   1 +
 codex-rs/tui/src/app/agents_overview_tests.rs |   2 +
 .../src/app/agents_overview_usage_tests.rs    |   1 +
 codex-rs/tui/src/app/daemon_menu_tests.rs     |   1 +
 codex-rs/tui/src/app/startup.rs               |   7 +
 .../src/app/tests/agents_navigation_tests.rs  |   5 +-
 .../src/app/tests/background_exit_tests.rs    |   1 +
 .../app/tests/navigation_reconnect_tests.rs   |   1 +
 .../app/tests/session_lifecycle_requests.rs   |   5 +
 codex-rs/tui/src/app/tests/startup.rs         |   1 +
 .../src/app/tests/startup_defaults_tests.rs   |   1 +
 .../worktree_background_terminals_tests.rs    |   1 +
 codex-rs/tui/src/app_server_connection.rs     |   3 +-
 .../experimental_features_view_tests.rs       |  21 ++
 ...s_view__tests__daemon_auto_start_menu.snap |  14 ++
 .../tui/src/chatwidget/rendering_tests.rs     |   1 +
 .../src/chatwidget/tests/slash_commands.rs    |   1 +
 codex-rs/tui/src/daemon_startup.rs            |   5 +-
 codex-rs/tui/src/daemon_startup_tests.rs      |  38 ++-
 codex-rs/tui/src/experimental_features.rs     |   3 +-
 .../tui/src/experimental_features_tests.rs    |   3 +
 .../external_agent_config_migration/flow.rs   |   2 +-
 ...ernal_agent_config_migration_messages.snap |   2 +-
 codex-rs/tui/src/history_cell/tests.rs        |   1 +
 codex-rs/tui/src/lib.rs                       |  34 ++-
 codex-rs/tui/src/session_start_tests.rs       |   1 +
 ...artup_tests__daemon_exclusion_warning.snap |   6 +
 codex-rs/tui/src/startup_orchestration.rs     |  60 ++++-
 codex-rs/tui/src/status/remote_connection.rs  |   7 +-
 codex-rs/tui/tests/suite/focus_palette.rs     |  55 +++++
 ...us_palette__daemon_auto_start_failure.snap |   7 +
 37 files changed, 513 insertions(+), 17 deletions(-)
 create mode 100644 codex-rs/cli/tests/daemon_startup.rs
 create mode 100644 codex-rs/tui/src/bottom_pane/snapshots/codex_tui__bottom_pane__experimental_features_view__tests__daemon_auto_start_menu.snap
 create mode 100644 codex-rs/tui/src/snapshots/codex_tui__daemon_startup_tests__daemon_exclusion_warning.snap
 create mode 100644 codex-rs/tui/tests/suite/snapshots/all__suite__focus_palette__daemon_auto_start_failure.snap

diff --git a/codex-rs/Cargo.lock b/codex-rs/Cargo.lock
index 86413b6d60..40385acfd3 100644
--- a/codex-rs/Cargo.lock
+++ b/codex-rs/Cargo.lock
@@ -2669,6 +2669,7 @@ dependencies = [
  "tracing-subscriber",
  "unicode-segmentation",
  "url",
+ "vt100",
  "which 8.0.0",
  "windows-sys 0.52.0",
  "wiremock",
@@ -4767,6 +4768,7 @@ dependencies = [
  "clap",
  "codex-ansi-escape",
  "codex-app-server-client",
+ "codex-app-server-daemon",
  "codex-app-server-protocol",
  "codex-arg0",
  "codex-backend-client",
diff --git a/codex-rs/cli/Cargo.toml b/codex-rs/cli/Cargo.toml
index 51181994e5..632147a701 100644
--- a/codex-rs/cli/Cargo.toml
+++ b/codex-rs/cli/Cargo.toml
@@ -129,6 +129,7 @@ pretty_assertions = { workspace = true }
 sqlx = { workspace = true }
 tar = { workspace = true }
 tokio-tungstenite = { workspace = true }
+vt100 = { workspace = true }
 wiremock = { workspace = true }
 zstd = { workspace = true }
 
diff --git a/codex-rs/cli/tests/daemon_startup.rs b/codex-rs/cli/tests/daemon_startup.rs
new file mode 100644
index 0000000000..309a665c12
--- /dev/null
+++ b/codex-rs/cli/tests/daemon_startup.rs
@@ -0,0 +1,217 @@
+//! Exercises daemon startup and excluded resume/fork pickers with Cargo's CLI executable.
+
+use anyhow::Context as _;
+use anyhow::Result;
+use anyhow::ensure;
+use std::collections::VecDeque;
+use std::fs;
+use std::process::Command;
+use std::time::Duration;
+
+#[tokio::test]
+#[cfg(unix)]
+async fn auto_daemon_start_attaches_to_shared_server() -> Result<()> {
+    daemon_startup("start").await
+}
+
+#[tokio::test]
+async fn daemon_exclusion_survives_resume_picker() -> Result<()> {
+    daemon_startup("resume").await
+}
+
+#[tokio::test]
+async fn daemon_exclusion_survives_fork_picker() -> Result<()> {
+    daemon_startup("fork").await
+}
+
+#[tokio::test]
+async fn daemon_auto_start_preserves_bedrock_onboarding() -> Result<()> {
+    daemon_startup("bedrock").await
+}
+
+#[tokio::test]
+#[cfg(unix)]
+async fn bedrock_onboarding_leaves_a_running_daemon_untouched() -> Result<()> {
+    daemon_startup("bedrock-running").await
+}
+
+async fn daemon_startup(command: &str) -> Result<()> {
+    let codex = codex_utils_cargo_bin::cargo_bin("codex")?.canonicalize()?;
+    let workspace = tempfile::tempdir()?;
+    let workspace_path = workspace.path().canonicalize()?;
+    #[cfg(unix)]
+    let home = tempfile::Builder::new().tempdir_in("/tmp")?;
+    #[cfg(not(unix))]
+    let home = tempfile::tempdir()?;
+    fs::write(
+        home.path().join("config.toml"),
+        format!(
+            "model = \"gpt-5.6-terra\"\nfeatures.daemon_auto_start = true\n\
+         features.bedrock_setup_wizard = true\ncli_auth_credentials_store = \"file\"\n\
+         suppress_unstable_features_warning = true\nanalytics.enabled = false\n\
+         windows.sandbox = \"unelevated\"\n\
+         tui.disable_paste_burst = true\n\
+         [projects.{}]\ntrust_level = \"trusted\"\n",
+            serde_json::to_string(&workspace_path)?,
+        ),
+    )?;
+    let bedrock_onboarding = matches!(command, "bedrock" | "bedrock-running");
+    if !bedrock_onboarding {
+        fs::write(
+            home.path().join("auth.json"),
+            r#"{"OPENAI_API_KEY":"daemon-startup-test","tokens":null,"last_refresh":null}"#,
+        )?;
+    }
+    let mut env = std::env::vars().collect::<std::collections::HashMap<_, _>>();
+    for key in [
+        "CODEX_EXEC_SERVER_URL",
+        "CODEX_ACCESS_TOKEN",
+        "CODEX_API_KEY",
+        "CODEX_CLOUD_TASKS_MODE",
+        "OPENAI_API_KEY",
+        "OPENAI_FEDERATION_RULE_ID",
+        "OPENAI_IDENTITY_TOKEN_FILE",
+        "OPENAI_WORKLOAD_IDENTITY_CONTEXT",
+    ] {
+        env.remove(key);
+    }
+    env.insert("CODEX_HOME".into(), home.path().display().to_string());
+    env.insert(
+        "CODEX_SQLITE_HOME".into(),
+        home.path().display().to_string(),
+    );
+    env.insert("TERM".into(), "xterm-256color".into());
+    let mut args = vec!["--no-alt-screen".to_string()];
+    let mut steps: VecDeque<(&str, &[u8])> = VecDeque::new();
+    if matches!(command, "start" | "bedrock-running") {
+        // A selected package with a stopped daemon avoids installing a release.
+        let managed = home
+            .path()
+            .join("packages/app-server-daemon/current/bin/codex");
+        fs::create_dir_all(home.path().join("packages/app-server-daemon/current/bin"))?;
+        fs::hard_link(&codex, &managed).or_else(|_| fs::copy(&codex, &managed).map(|_| ()))?;
+        fs::create_dir(home.path().join("app-server-daemon"))?;
+        fs::write(
+            home.path().join("app-server-daemon/settings.json"),
+            r#"{"shutdownGraceSeconds":0,"updater":{"autoUpdateEnabled":false}}"#,
+        )?;
+    }
+    let pid_file = home.path().join("app-server-daemon/daemon.pid");
+    let result = async {
+        let existing_daemon = if command == "bedrock-running" {
+            let started = Command::new(&codex)
+                .env_clear()
+                .envs(&env)
+                .current_dir(&workspace_path)
+                .args(["app-server", "daemon", "start"])
+                .output()?;
+            ensure!(
+                started.status.success(),
+                "{}",
+                String::from_utf8_lossy(&started.stderr)
+            );
+            Some(fs::read(&pid_file)?)
+        } else {
+            None
+        };
+        let expected = if command == "start" {
+            // The draft header is visible before the session's command composer is ready.
+            steps.push_back(("gpt-5.6-terra", b"/status\r"));
+            "app-server-control.sock"
+        } else if bedrock_onboarding {
+            "UseAmazonBedrock"
+        } else {
+            args.extend([command.into(), "--strict-config".into()]);
+            steps.push_back(("Nosessionsyet", b"\x1b"));
+            steps.push_back(("gpt-5.6-terra", b"\x14"));
+            "Runningwithoutthesharedbackgroundserver:--strict-config"
+        };
+        let spawned = codex_utils_pty::spawn_pty_process(
+            &codex.to_string_lossy(),
+            &args,
+            &workspace_path,
+            &env,
+            /*arg0*/ &None,
+            codex_utils_pty::TerminalSize {
+                rows: 40,
+                cols: 120,
+            },
+            &[],
+        )
+        .await?;
+        let session = spawned.session;
+        let writer = session.writer_sender();
+        let mut stdout = spawned.stdout_rx;
+        let mut output = String::new();
+        let mut screen = vt100::Parser::new(
+            /*rows*/ 40, /*cols*/ 120, /*scrollback_len*/ 0,
+        );
+        let mut queries: Vec<(&str, &[u8])> = vec![
+            ("\x1b[6n", b"\x1b[1;1R"),
+            ("\x1b[?u", b"\x1b[?0u\x1b[?1;2c"),
+            ("\x1b[c", b"\x1b[?1;2c"),
+            ("\x1b]10;?", b"\x1b]10;rgb:ffff/ffff/ffff\x1b\\"),
+            ("\x1b]11;?", b"\x1b]11;rgb:0000/0000/0000\x1b\\"),
+        ];
+        let result = tokio::time::timeout(Duration::from_secs(/*secs*/ 45), async {
+            while let Some(bytes) = stdout.recv().await {
+                output.push_str(&String::from_utf8_lossy(&bytes));
+                screen.process(&bytes);
+                for (query, reply) in &mut queries {
+                    if !query.is_empty() && output.contains(*query) {
+                        writer.send(reply.to_vec()).await?;
+                        *query = "";
+                    }
+                }
+                let text: String = screen
+                    .screen()
+                    .contents()
+                    .chars()
+                    .filter(|c| !c.is_whitespace())
+                    .collect();
+                if let Some((ready, input)) = steps.front()
+                    && text.contains(ready)
+                {
+                    writer.send(input.to_vec()).await?;
+                    steps.pop_front();
+                    output.clear();
+                } else if steps.is_empty() && text.contains(expected) {
+                    if command == "start" {
+                        ensure!(text.contains("unix://"));
+                        ensure!(home.path().join("app-server-daemon/daemon.pid").exists());
+                    } else if let Some(existing_daemon) = &existing_daemon {
+                        ensure!(fs::read(&pid_file)? == *existing_daemon);
+                    } else if bedrock_onboarding {
+                        ensure!(!pid_file.exists());
+                    }
+                    return Ok::<_, anyhow::Error>(());
+                }
+            }
+            anyhow::bail!(
+                "TUI exited before {expected}: {}",
+                screen.screen().contents()
+            )
+        })
+        .await;
+        Ok::<_, anyhow::Error>((
+            session,
+            result.with_context(|| format!("{command} timed out: {}", screen.screen().contents())),
+        ))
+    }
+    .await;
+    // Always stop the detached daemon, including on timeout or failed assertions.
+    let stopped = Command::new(&codex)
+        .env_clear()
+        .envs(&env)
+        .args(["app-server", "daemon", "stop"])
+        .output()?;
+    let (session, result) = result?;
+    session.terminate();
+    result??;
+    ensure!(
+        stopped.status.success(),
+        "{}",
+        String::from_utf8_lossy(&stopped.stderr)
+    );
+    Ok(())
+}
diff --git a/codex-rs/core/config.schema.json b/codex-rs/core/config.schema.json
index e53a95e2d5..92d7ebf324 100644
--- a/codex-rs/core/config.schema.json
+++ b/codex-rs/core/config.schema.json
@@ -757,6 +757,9 @@
             "cwd_relative_turn_diffs": {
               "type": "boolean"
             },
+            "daemon_auto_start": {
+              "type": "boolean"
+            },
             "default_mode_request_user_input": {
               "type": "boolean"
             },
@@ -6411,6 +6414,9 @@
         "cwd_relative_turn_diffs": {
           "type": "boolean"
         },
+        "daemon_auto_start": {
+          "type": "boolean"
+        },
         "default_mode_request_user_input": {
           "type": "boolean"
         },
diff --git a/codex-rs/features/src/lib.rs b/codex-rs/features/src/lib.rs
index 557a9dfb17..a8cabd702c 100644
--- a/codex-rs/features/src/lib.rs
+++ b/codex-rs/features/src/lib.rs
@@ -110,6 +110,8 @@ pub enum Feature {
     SecretAuthStorage,
 
     // Experimental
+    /// Automatically start the shared local daemon for eligible interactive launches.
+    DaemonAutoStart,
     /// Send per-content-entry classifications in internal Responses metadata.
     ContentItemKinds,
     /// Record model-attempted tool calls in internal Responses metadata.
@@ -920,6 +922,16 @@ pub const FEATURES: &[FeatureSpec] = &[
         },
         default_enabled: false,
     },
+    FeatureSpec {
+        id: Feature::DaemonAutoStart,
+        key: "daemon_auto_start",
+        stage: Stage::Experimental {
+            name: "Automatically start the background server",
+            menu_description: "Use the shared local server for new, resumed, and forked sessions. Takes effect next launch.",
+            announcement: "Automatic background server startup can now be enabled from /experimental.",
+        },
+        default_enabled: false,
+    },
     FeatureSpec {
         id: Feature::TranscriptV2,
         key: "transcript_v2",
diff --git a/codex-rs/tui/Cargo.toml b/codex-rs/tui/Cargo.toml
index 2ed86100bb..70f7bcf562 100644
--- a/codex-rs/tui/Cargo.toml
+++ b/codex-rs/tui/Cargo.toml
@@ -30,6 +30,7 @@ chrono = { workspace = true, features = ["serde"] }
 clap = { workspace = true, features = ["derive"] }
 codex-ansi-escape = { workspace = true }
 codex-app-server-client = { workspace = true }
+codex-app-server-daemon = { workspace = true }
 codex-app-server-protocol = { workspace = true }
 codex-arg0 = { workspace = true }
 codex-backend-client = { workspace = true }
diff --git a/codex-rs/tui/src/app/agents_overview_actions_tests.rs b/codex-rs/tui/src/app/agents_overview_actions_tests.rs
index 835a4a4367..44facee704 100644
--- a/codex-rs/tui/src/app/agents_overview_actions_tests.rs
+++ b/codex-rs/tui/src/app/agents_overview_actions_tests.rs
@@ -510,6 +510,7 @@ async fn lifecycle_removes_background_and_current_tasks_without_losing_the_dashb
             )),
         );
         app.app_server_target = AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: crate::RemoteAppServerEndpoint::UnixSocket {
                 socket_path: test_path_buf("/tmp/unused.sock").abs(),
             },
diff --git a/codex-rs/tui/src/app/agents_overview_tests.rs b/codex-rs/tui/src/app/agents_overview_tests.rs
index f1ebf9250a..837abc3327 100644
--- a/codex-rs/tui/src/app/agents_overview_tests.rs
+++ b/codex-rs/tui/src/app/agents_overview_tests.rs
@@ -495,6 +495,7 @@ async fn shared_overview_seeds_once_and_retains_locally_resumed_history() -> Res
     )
     .expect("materialize unindexed session");
     app.app_server_target = AppServerTarget::LocalDaemon {
+        allow_embedded_fallback: true,
         endpoint: crate::RemoteAppServerEndpoint::UnixSocket {
             socket_path: test_path_buf("/tmp/unused.sock").abs(),
         },
@@ -2335,6 +2336,7 @@ async fn command_center_attach_conflict_opens_read_only_and_retries() -> Result<
         .await?;
     let mut server = Box::pin(crate::start_embedded_app_server_for_picker(&app.config)).await?;
     app.app_server_target = AppServerTarget::LocalDaemon {
+        allow_embedded_fallback: true,
         endpoint: crate::resolve_remote_addr("ws://127.0.0.1:4500")?,
     };
     app.chat_widget.remote_connection =
diff --git a/codex-rs/tui/src/app/agents_overview_usage_tests.rs b/codex-rs/tui/src/app/agents_overview_usage_tests.rs
index 467c3df01b..8608be3e79 100644
--- a/codex-rs/tui/src/app/agents_overview_usage_tests.rs
+++ b/codex-rs/tui/src/app/agents_overview_usage_tests.rs
@@ -200,6 +200,7 @@ async fn selected_usage_is_cached_and_account_changes_discard_old_results() -> R
     app.agents_overview.usage_disabled = true;
     app.agents_overview.pending_usage = Some((thread_id, request_id));
     app.app_server_target = AppServerTarget::LocalDaemon {
+        allow_embedded_fallback: true,
         endpoint: crate::RemoteAppServerEndpoint::UnixSocket {
             socket_path: test_path_buf("/tmp/test.sock").abs(),
         },
diff --git a/codex-rs/tui/src/app/daemon_menu_tests.rs b/codex-rs/tui/src/app/daemon_menu_tests.rs
index 8991b49309..ffb5eeb0c0 100644
--- a/codex-rs/tui/src/app/daemon_menu_tests.rs
+++ b/codex-rs/tui/src/app/daemon_menu_tests.rs
@@ -18,6 +18,7 @@ async fn daemon_menu_is_read_only_and_confirmation_can_cancel_or_handoff() {
     app.daemon_cli_executable =
         Some(AbsolutePathBuf::from_absolute_path(package.path().join("bin/codex")).unwrap());
     app.app_server_target = AppServerTarget::LocalDaemon {
+        allow_embedded_fallback: true,
         endpoint: crate::RemoteAppServerEndpoint::UnixSocket {
             socket_path: AbsolutePathBuf::relative_to_current_dir("codex.sock").unwrap(),
         },
diff --git a/codex-rs/tui/src/app/startup.rs b/codex-rs/tui/src/app/startup.rs
index d7ae69c7b8..3952d213c4 100644
--- a/codex-rs/tui/src/app/startup.rs
+++ b/codex-rs/tui/src/app/startup.rs
@@ -154,6 +154,7 @@ impl App {
         startup_elapsed_before_app: Duration,
         startup_bootstrap: Option<AppServerBootstrap>,
         startup_hooks_browser: Option<HooksListEntry>,
+        daemon_startup_warning: Option<String>,
         mut startup_draft: StartupDraftPump,
         managed_worktree: Option<crate::ManagedTuiWorktree>,
         daemon_cli_executable: Option<AbsolutePathBuf>,
@@ -698,6 +699,12 @@ impl App {
                     started.session.windows_sandbox_host
                 })
         };
+        // This launch warning belongs to the TUI, independent of picker/trust client replacement.
+        if let Some(warning) = daemon_startup_warning {
+            app_event_tx.send(AppEvent::InsertHistoryCell(Box::new(
+                history_cell::StartupWarningsCell::new(vec![warning]),
+            )));
+        }
         let file_search = FileSearchManager::new(config.cwd.to_path_buf(), app_event_tx.clone());
         let runtime_keymap =
             RuntimeKeymap::from_config(&local_settings.tui.keymap).map_err(|err| {
diff --git a/codex-rs/tui/src/app/tests/agents_navigation_tests.rs b/codex-rs/tui/src/app/tests/agents_navigation_tests.rs
index 1daac6c13e..e9424e8c9b 100644
--- a/codex-rs/tui/src/app/tests/agents_navigation_tests.rs
+++ b/codex-rs/tui/src/app/tests/agents_navigation_tests.rs
@@ -14,7 +14,10 @@ async fn agents_navigation_requires_local_daemon() -> Result<()> {
         AppServerTarget::Remote {
             endpoint: endpoint.clone(),
         },
-        AppServerTarget::LocalDaemon { endpoint },
+        AppServerTarget::LocalDaemon {
+            endpoint,
+            allow_embedded_fallback: true,
+        },
     ] {
         let enabled = matches!(target, AppServerTarget::LocalDaemon { .. });
         app.app_server_target = target;
diff --git a/codex-rs/tui/src/app/tests/background_exit_tests.rs b/codex-rs/tui/src/app/tests/background_exit_tests.rs
index 911af0c7f8..378eff923a 100644
--- a/codex-rs/tui/src/app/tests/background_exit_tests.rs
+++ b/codex-rs/tui/src/app/tests/background_exit_tests.rs
@@ -164,6 +164,7 @@ async fn embedded_exit_keeps_the_session_summary() {
 
 fn prepare_local_daemon_thread(app: &mut App) -> Result<ThreadId> {
     app.app_server_target = AppServerTarget::LocalDaemon {
+        allow_embedded_fallback: true,
         endpoint: crate::RemoteAppServerEndpoint::UnixSocket {
             socket_path: AbsolutePathBuf::relative_to_current_dir("codex.sock")?,
         },
diff --git a/codex-rs/tui/src/app/tests/navigation_reconnect_tests.rs b/codex-rs/tui/src/app/tests/navigation_reconnect_tests.rs
index a83dd9c085..874f2af411 100644
--- a/codex-rs/tui/src/app/tests/navigation_reconnect_tests.rs
+++ b/codex-rs/tui/src/app/tests/navigation_reconnect_tests.rs
@@ -158,6 +158,7 @@ async fn reconnect_daemon_command_center_after_socket_replacement_without_a_conv
             socket_path: codex_utils_absolute_path::AbsolutePathBuf::try_from(socket_path.clone())?,
         };
         app.app_server_target = AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: endpoint.clone(),
         };
         let interrupted_setup = previous_thread.is_none() && !overview_initialized;
diff --git a/codex-rs/tui/src/app/tests/session_lifecycle_requests.rs b/codex-rs/tui/src/app/tests/session_lifecycle_requests.rs
index be68e78b0b..aad1b59261 100644
--- a/codex-rs/tui/src/app/tests/session_lifecycle_requests.rs
+++ b/codex-rs/tui/src/app/tests/session_lifecycle_requests.rs
@@ -678,6 +678,7 @@ async fn delete_current_thread_navigates_only_after_success() -> Result<()> {
     for target in [
         AppServerTarget::Embedded,
         AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: endpoint.clone(),
         },
         AppServerTarget::Remote { endpoint },
@@ -984,6 +985,7 @@ async fn archive_current_thread_returns_shared_servers_to_agents() -> Result<()>
     let endpoint = crate::resolve_remote_addr("ws://127.0.0.1:4500")?;
     for target in [
         AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: endpoint.clone(),
         },
         AppServerTarget::Remote { endpoint },
@@ -2898,6 +2900,7 @@ async fn agents_overview_seeds_loaded_threads_when_recent_listing_is_unavailable
         .await?;
         let started = app_server.start_thread(&app.config).await?;
         app.app_server_target = AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: crate::RemoteAppServerEndpoint::UnixSocket {
                 socket_path: test_path_buf("/tmp/unused.sock").abs(),
             },
@@ -4433,6 +4436,7 @@ async fn external_writer_escape_preserves_snapshot_and_explicit_quits() -> Resul
     let endpoint = crate::resolve_remote_addr("ws://127.0.0.1:4500")?;
     for target in [
         AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: endpoint.clone(),
         },
         AppServerTarget::Remote { endpoint },
@@ -4616,6 +4620,7 @@ async fn command_center_read_only_open_requests_and_failure_preservation() -> Re
         )
         .await?;
         app.app_server_target = AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: crate::resolve_remote_addr("ws://127.0.0.1:4500")?,
         };
         let current = Box::pin(server.start_thread(&app.config)).await?;
diff --git a/codex-rs/tui/src/app/tests/startup.rs b/codex-rs/tui/src/app/tests/startup.rs
index cd875484d7..0358ef3ecc 100644
--- a/codex-rs/tui/src/app/tests/startup.rs
+++ b/codex-rs/tui/src/app/tests/startup.rs
@@ -28,6 +28,7 @@ async fn windows_sandbox_setup_uses_local_app_server_connection() {
         auth_token: None,
     };
     app.app_server_target = crate::AppServerTarget::LocalDaemon {
+        allow_embedded_fallback: true,
         endpoint: endpoint.clone(),
     };
     assert!(app.windows_sandbox_setup_is_local());
diff --git a/codex-rs/tui/src/app/tests/startup_defaults_tests.rs b/codex-rs/tui/src/app/tests/startup_defaults_tests.rs
index 4d3ee2165a..811db659dc 100644
--- a/codex-rs/tui/src/app/tests/startup_defaults_tests.rs
+++ b/codex-rs/tui/src/app/tests/startup_defaults_tests.rs
@@ -33,6 +33,7 @@ async fn run_startup_for_test(
         Duration::ZERO,
         Some(bootstrap),
         /*startup_hooks_browser*/ None,
+        /*daemon_startup_warning*/ None,
         crate::startup_draft::tests::quiet_startup_test_pump(),
         /*managed_worktree*/ None,
         /*daemon_cli_executable*/ None,
diff --git a/codex-rs/tui/src/app/tests/worktree_background_terminals_tests.rs b/codex-rs/tui/src/app/tests/worktree_background_terminals_tests.rs
index 6f6e0e1db7..71351534ae 100644
--- a/codex-rs/tui/src/app/tests/worktree_background_terminals_tests.rs
+++ b/codex-rs/tui/src/app/tests/worktree_background_terminals_tests.rs
@@ -6,6 +6,7 @@ use pretty_assertions::assert_eq;
 #[test]
 fn old_local_daemon_worktree_error_suggests_update() -> Result<()> {
     let target = AppServerTarget::LocalDaemon {
+        allow_embedded_fallback: true,
         endpoint: crate::RemoteAppServerEndpoint::UnixSocket {
             socket_path: AbsolutePathBuf::relative_to_current_dir("codex.sock")?,
         },
diff --git a/codex-rs/tui/src/app_server_connection.rs b/codex-rs/tui/src/app_server_connection.rs
index 8df6681e7e..ac3ab1cb2c 100644
--- a/codex-rs/tui/src/app_server_connection.rs
+++ b/codex-rs/tui/src/app_server_connection.rs
@@ -22,6 +22,7 @@ pub(crate) async fn connect(target: &AppServerTarget) -> color_eyre::Result<AppS
         #[cfg(windows)]
         AppServerTarget::LocalDaemon {
             endpoint: RemoteAppServerEndpoint::UnixSocket { socket_path },
+            ..
         } => {
             // Revalidate at the real connection, not just the earlier discovery probe.
             let (socket_path, _directory) =
@@ -41,7 +42,7 @@ pub(crate) async fn connect(target: &AppServerTarget) -> color_eyre::Result<AppS
                 .await?;
             Ok(AppServerClient::Remote(app_server))
         }
-        AppServerTarget::LocalDaemon { endpoint } | AppServerTarget::Remote { endpoint } => {
+        AppServerTarget::LocalDaemon { endpoint, .. } | AppServerTarget::Remote { endpoint } => {
             connect_remote_app_server(endpoint.clone()).await
         }
     }
diff --git a/codex-rs/tui/src/bottom_pane/experimental_features_view_tests.rs b/codex-rs/tui/src/bottom_pane/experimental_features_view_tests.rs
index bd8660426e..c9b2ee4129 100644
--- a/codex-rs/tui/src/bottom_pane/experimental_features_view_tests.rs
+++ b/codex-rs/tui/src/bottom_pane/experimental_features_view_tests.rs
@@ -257,3 +257,24 @@ fn voice_discovery_requires_the_client_runtime() {
         );
     }
 }
+
+#[test]
+fn daemon_auto_start_menu_snapshot() {
+    let feature = Feature::DaemonAutoStart;
+    let stage = feature.stage();
+    let (app_tx, _app_rx) = tokio::sync::mpsc::unbounded_channel();
+    let view = ExperimentalFeaturesView::new(
+        vec![ExperimentalFeatureItem {
+            key: feature.key().to_string(),
+            name: stage.experimental_menu_name().unwrap().to_string(),
+            description: stage.experimental_menu_description().unwrap().to_string(),
+            enabled: feature.default_enabled(),
+            writable: true,
+        }],
+        ThreadId::new(),
+        /*catalog_rx*/ None,
+        AppEventSender::new(app_tx),
+        crate::keymap::RuntimeKeymap::defaults().list,
+    );
+    snapshot_view("daemon_auto_start_menu", &view);
+}
diff --git a/codex-rs/tui/src/bottom_pane/snapshots/codex_tui__bottom_pane__experimental_features_view__tests__daemon_auto_start_menu.snap b/codex-rs/tui/src/bottom_pane/snapshots/codex_tui__bottom_pane__experimental_features_view__tests__daemon_auto_start_menu.snap
new file mode 100644
index 0000000000..7627e249b9
--- /dev/null
+++ b/codex-rs/tui/src/bottom_pane/snapshots/codex_tui__bottom_pane__experimental_features_view__tests__daemon_auto_start_menu.snap
@@ -0,0 +1,14 @@
+---
+source: tui/src/bottom_pane/experimental_features_view_tests.rs
+expression: buffer_text(&buffer)
+---
+  Experimental features
+  Checked features are configured on. Some experimental features take effect
+  only in new tasks or after restarting the Codex server.
+
+› [ ] Automatically start the background server  Use the shared local server
+                                                 for new, resumed, and forked
+                                                 sessions. Takes effect next
+                                                 launch.
+
+  Press space to select or enter to save
diff --git a/codex-rs/tui/src/chatwidget/rendering_tests.rs b/codex-rs/tui/src/chatwidget/rendering_tests.rs
index 902bc0ec55..333f3146f6 100644
--- a/codex-rs/tui/src/chatwidget/rendering_tests.rs
+++ b/codex-rs/tui/src/chatwidget/rendering_tests.rs
@@ -373,6 +373,7 @@ async fn external_writer_notice_offers_command_center_on_shared_servers() {
     let endpoint = crate::resolve_remote_addr("ws://127.0.0.1:4500").unwrap();
     for target in [
         crate::AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: endpoint.clone(),
         },
         crate::AppServerTarget::Remote { endpoint },
diff --git a/codex-rs/tui/src/chatwidget/tests/slash_commands.rs b/codex-rs/tui/src/chatwidget/tests/slash_commands.rs
index 7056100445..79d4d4d3d0 100644
--- a/codex-rs/tui/src/chatwidget/tests/slash_commands.rs
+++ b/codex-rs/tui/src/chatwidget/tests/slash_commands.rs
@@ -2832,6 +2832,7 @@ async fn slash_delete_confirmation_requests_current_thread_delete() {
     for target in [
         crate::AppServerTarget::Embedded,
         crate::AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: endpoint.clone(),
         },
         crate::AppServerTarget::Remote { endpoint },
diff --git a/codex-rs/tui/src/daemon_startup.rs b/codex-rs/tui/src/daemon_startup.rs
index 20a189cc0e..d37bce9407 100644
--- a/codex-rs/tui/src/daemon_startup.rs
+++ b/codex-rs/tui/src/daemon_startup.rs
@@ -1,7 +1,10 @@
-//! Local daemon discovery policy. Explicit embedded launches never probe the shared server.
+//! Local daemon launch policy. Explicit embedded launches never discover or start a daemon;
+//! automatic launches require a successful shared-server connection.
 
 use super::*;
 
+pub(super) const FAILURE_HINT: &str = "To work without the background server, rerun the same command with --no-daemon (including resume or fork and its arguments).";
+
 pub(super) fn exclusion(
     cli: &Cli,
     cli_kv_overrides: &[(String, toml::Value)],
diff --git a/codex-rs/tui/src/daemon_startup_tests.rs b/codex-rs/tui/src/daemon_startup_tests.rs
index 49725cbb92..48fe876481 100644
--- a/codex-rs/tui/src/daemon_startup_tests.rs
+++ b/codex-rs/tui/src/daemon_startup_tests.rs
@@ -1,4 +1,4 @@
-//! Implicit daemon discovery is opportunistic; explicit endpoints remain authoritative.
+//! Opportunistic attachment may fall back; automatic startup requires a shared server.
 
 use super::*;
 use crate::legacy_core::config::ConfigBuilder;
@@ -14,6 +14,7 @@ async fn daemon_connection_rejects_unprotected_socket_before_handshake() -> colo
     let socket_path = AbsolutePathBuf::from_absolute_path_checked(parent.join("server.sock"))?;
     let mut listener = codex_uds::UnixListener::bind(socket_path.as_path()).await?;
     let target = AppServerTarget::LocalDaemon {
+        allow_embedded_fallback: true,
         endpoint: RemoteAppServerEndpoint::UnixSocket { socket_path },
     };
     tokio::select! {
@@ -25,7 +26,12 @@ async fn daemon_connection_rejects_unprotected_socket_before_handshake() -> colo
 
 #[tokio::test]
 async fn daemon_startup_falls_back_only_for_implicit_endpoints() -> color_eyre::Result<()> {
-    for scenario in ["missing socket", "failed handshake", "explicit endpoint"] {
+    for scenario in [
+        "missing socket",
+        "failed handshake",
+        "explicit endpoint",
+        "required daemon",
+    ] {
         let home = TempDir::new()?;
         let config = ConfigBuilder::default()
             .codex_home(home.path().to_path_buf())
@@ -50,7 +56,10 @@ async fn daemon_startup_falls_back_only_for_implicit_endpoints() -> color_eyre::
         let mut target = if scenario == "explicit endpoint" {
             AppServerTarget::Remote { endpoint }
         } else {
-            AppServerTarget::LocalDaemon { endpoint }
+            AppServerTarget::LocalDaemon {
+                endpoint,
+                allow_embedded_fallback: scenario != "required daemon",
+            }
         };
         let original_target = target.clone();
         let mut state_db = None;
@@ -69,8 +78,13 @@ async fn daemon_startup_falls_back_only_for_implicit_endpoints() -> color_eyre::
         )
         .await;
         reject_handshake.abort();
-        if scenario == "explicit endpoint" {
+        if scenario == "explicit endpoint" || scenario == "required daemon" {
             assert!(result.is_err());
+            if scenario == "required daemon" {
+                let message = result.err().unwrap().to_string();
+                assert!(message.contains("rerun the same command with --no-daemon"));
+                assert!(message.contains("failed to connect to remote app server"));
+            }
             assert_eq!(target, original_target);
             assert!(state_db.is_none());
         } else {
@@ -162,3 +176,19 @@ fn daemon_eligibility_preserves_launch_options_and_explains_exclusions() {
         None
     );
 }
+
+#[test]
+fn daemon_exclusion_warning_snapshot() {
+    use crate::history_cell::HistoryCell;
+    let cell = crate::history_cell::StartupWarningsCell::new(vec![
+        "Running without the shared background server: --strict-config requires embedded mode."
+            .into(),
+    ]);
+    let text = cell
+        .transcript_lines(/*width*/ 80)
+        .iter()
+        .map(ToString::to_string)
+        .collect::<Vec<_>>()
+        .join("\n");
+    insta::assert_snapshot!("daemon_exclusion_warning", text);
+}
diff --git a/codex-rs/tui/src/experimental_features.rs b/codex-rs/tui/src/experimental_features.rs
index dee31a7713..6cb5887f36 100644
--- a/codex-rs/tui/src/experimental_features.rs
+++ b/codex-rs/tui/src/experimental_features.rs
@@ -108,7 +108,8 @@ pub(crate) async fn write(
             let key = format!("features.{}", serde_json::json!(name));
             Ok(crate::config_update::replace_config_value(
                 key,
-                if *enabled || feature.default_enabled {
+                // Keep the daemon opt-out explicit even before rollout defaults enable it.
+                if *enabled || feature.default_enabled || name == "daemon_auto_start" {
                     serde_json::json!(enabled)
                 } else {
                     serde_json::Value::Null
diff --git a/codex-rs/tui/src/experimental_features_tests.rs b/codex-rs/tui/src/experimental_features_tests.rs
index a5f6797f72..987b8bcdb8 100644
--- a/codex-rs/tui/src/experimental_features_tests.rs
+++ b/codex-rs/tui/src/experimental_features_tests.rs
@@ -180,6 +180,7 @@ async fn experimental_feature_writes_use_server_defaults_and_refresh_configured_
                     "initialize" => json!({"userAgent": "experimental-test"}),
                     "experimentalFeature/list" => {
                         json!({"data": [
+                            {"name": "daemon_auto_start", "stage": "beta", "displayName": null, "description": null, "announcement": null, "enabled": !wrote || scenario == "overridden", "defaultEnabled": false},
                             {"name": "default_off", "stage": "beta", "displayName": null, "description": null, "announcement": null, "enabled": !wrote || scenario == "overridden", "defaultEnabled": false},
                             {"name": "default_on", "stage": "beta", "displayName": null, "description": null, "announcement": null, "enabled": !wrote, "defaultEnabled": true},
                             {"name": "new_server_feature", "stage": "beta", "displayName": null, "description": null, "announcement": null, "enabled": wrote, "defaultEnabled": false}
@@ -190,6 +191,7 @@ async fn experimental_feature_writes_use_server_defaults_and_refresh_configured_
                             request.params,
                             Some(json!({
                                 "edits": [
+                                    {"keyPath": "features.\"daemon_auto_start\"", "value": false, "mergeStrategy": "replace"},
                                     {"keyPath": "features.\"default_off\"", "value": null, "mergeStrategy": "replace"},
                                     {"keyPath": "features.\"default_on\"", "value": false, "mergeStrategy": "replace"},
                                     {"keyPath": "features.\"new_server_feature\"", "value": true, "mergeStrategy": "replace"}
@@ -226,6 +228,7 @@ async fn experimental_feature_writes_use_server_defaults_and_refresh_configured_
             handle,
             thread_id,
             vec![
+                ("daemon_auto_start".to_string(), false),
                 ("default_off".to_string(), false),
                 ("default_on".to_string(), false),
                 ("new_server_feature".to_string(), true),
diff --git a/codex-rs/tui/src/external_agent_config_migration/flow.rs b/codex-rs/tui/src/external_agent_config_migration/flow.rs
index 1bbddee3dd..ebaf050519 100644
--- a/codex-rs/tui/src/external_agent_config_migration/flow.rs
+++ b/codex-rs/tui/src/external_agent_config_migration/flow.rs
@@ -19,7 +19,7 @@ use super::source::run_external_agent_config_source_prompt;
 pub(crate) const EXTERNAL_AGENT_CONFIG_MIGRATION_NO_ITEMS_MESSAGE: &str =
     "No compatible setup was found to import.";
 pub(crate) const EXTERNAL_AGENT_CONFIG_MIGRATION_REMOTE_UNAVAILABLE_MESSAGE: &str = "Import from other apps is unavailable in remote sessions. Start Codex locally and run /import.";
-pub(crate) const EXTERNAL_AGENT_CONFIG_MIGRATION_DAEMON_UNAVAILABLE_MESSAGE: &str = "Import from other apps is unavailable while Codex is connected to the local app-server daemon. Stop the daemon, restart Codex, and run /import.";
+pub(crate) const EXTERNAL_AGENT_CONFIG_MIGRATION_DAEMON_UNAVAILABLE_MESSAGE: &str = "Import from other apps is unavailable while Codex is connected to the local app-server daemon. Restart with `codex --no-daemon` and run /import.";
 
 pub(crate) enum ExternalAgentConfigMigrationFlowOutcome {
     Started(Vec<Line<'static>>),
diff --git a/codex-rs/tui/src/external_agent_config_migration/snapshots/codex_tui__external_agent_config_migration__flow__tests__external_agent_config_migration_messages.snap b/codex-rs/tui/src/external_agent_config_migration/snapshots/codex_tui__external_agent_config_migration__flow__tests__external_agent_config_migration_messages.snap
index 59a70e4e0e..04d7038b3c 100644
--- a/codex-rs/tui/src/external_agent_config_migration/snapshots/codex_tui__external_agent_config_migration__flow__tests__external_agent_config_migration_messages.snap
+++ b/codex-rs/tui/src/external_agent_config_migration/snapshots/codex_tui__external_agent_config_migration__flow__tests__external_agent_config_migration_messages.snap
@@ -39,5 +39,5 @@ expression: messages
   Run /import again to check for additional items.
 No compatible setup was found to import.
 Import from other apps is unavailable in remote sessions. Start Codex locally and run /import.
-Import from other apps is unavailable while Codex is connected to the local app-server daemon. Stop the daemon, restart Codex, and run /import.
+Import from other apps is unavailable while Codex is connected to the local app-server daemon. Restart with `codex --no-daemon` and run /import.
 A previous external agent import is still running. Wait for it to finish before importing again.
diff --git a/codex-rs/tui/src/history_cell/tests.rs b/codex-rs/tui/src/history_cell/tests.rs
index 5bef8f1e93..e038520521 100644
--- a/codex-rs/tui/src/history_cell/tests.rs
+++ b/codex-rs/tui/src/history_cell/tests.rs
@@ -66,6 +66,7 @@ fn connected_server_version_notice_snapshot() {
 #[test]
 fn local_daemon_version_notice_snapshot() {
     let target = crate::AppServerTarget::LocalDaemon {
+        allow_embedded_fallback: true,
         endpoint: crate::RemoteAppServerEndpoint::UnixSocket {
             socket_path: AbsolutePathBuf::from_absolute_path(
                 std::env::temp_dir().join("codex.sock"),
diff --git a/codex-rs/tui/src/lib.rs b/codex-rs/tui/src/lib.rs
index 7c00ce4c50..013231e6c8 100644
--- a/codex-rs/tui/src/lib.rs
+++ b/codex-rs/tui/src/lib.rs
@@ -299,8 +299,13 @@ async fn start_embedded_app_server(
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub(crate) enum AppServerTarget {
     Embedded,
-    LocalDaemon { endpoint: RemoteAppServerEndpoint },
-    Remote { endpoint: RemoteAppServerEndpoint },
+    LocalDaemon {
+        endpoint: RemoteAppServerEndpoint,
+        allow_embedded_fallback: bool,
+    },
+    Remote {
+        endpoint: RemoteAppServerEndpoint,
+    },
 }
 
 impl AppServerTarget {
@@ -517,11 +522,25 @@ async fn start_app_server(
     if let Some(connection) = connection {
         match connection {
             Ok(app_server) => return Ok(app_server),
-            Err(err) if matches!(target, AppServerTarget::LocalDaemon { .. }) => {
+            Err(err)
+                if matches!(
+                    target,
+                    AppServerTarget::LocalDaemon {
+                        allow_embedded_fallback: true,
+                        ..
+                    }
+                ) =>
+            {
                 tracing::debug!(%err, "local daemon connection failed; starting embedded app server");
                 *target = AppServerTarget::Embedded;
                 *state_db = init_state_db_for_app_server_target(&config, target).await?;
             }
+            Err(err) if matches!(target, AppServerTarget::LocalDaemon { .. }) => {
+                return Err(color_eyre::eyre::eyre!(
+                    "{err:#}\n{}",
+                    daemon_startup::FAILURE_HINT
+                ));
+            }
             Err(err) => return Err(err),
         }
     }
@@ -948,6 +967,7 @@ fn app_server_target_for_launch(
         None if can_reuse_implicit_local_daemon && exec_server_url.is_none() => {
             default_daemon_socket.map_or(AppServerTarget::Embedded, |socket_path| {
                 AppServerTarget::LocalDaemon {
+                    allow_embedded_fallback: true,
                     endpoint: RemoteAppServerEndpoint::UnixSocket { socket_path },
                 }
             })
@@ -1040,6 +1060,7 @@ async fn run_ratatui_app(
     mut state_db: Option<StateDbHandle>,
     environment_manager: Arc<EnvironmentManager>,
     managed_worktree: Option<ManagedTuiWorktree>,
+    daemon_startup_warning: Option<String>,
     startup_draft: startup_draft::StartupDraft,
 ) -> color_eyre::Result<AppExitInfo> {
     let uses_remote_workspace = app_server_target.uses_remote_workspace();
@@ -1896,6 +1917,7 @@ async fn run_ratatui_app(
         startup_elapsed_before_app,
         startup_bootstrap,
         startup_hooks_browser,
+        daemon_startup_warning,
         startup_draft,
         managed_worktree,
         daemon_cli_executable,
@@ -2291,6 +2313,7 @@ requires_openai_auth = {requires_openai_auth}
                 enabled,
                 LoginStatus::NotAuthenticated,
                 AppServerTarget::LocalDaemon {
+                    allow_embedded_fallback: true,
                     endpoint: shared_endpoint.clone(),
                 },
                 false,
@@ -2911,6 +2934,7 @@ requires_openai_auth = {requires_openai_auth}
         assert_eq!(
             target,
             AppServerTarget::LocalDaemon {
+                allow_embedded_fallback: true,
                 endpoint: RemoteAppServerEndpoint::UnixSocket { socket_path },
             }
         );
@@ -3012,6 +3036,7 @@ requires_openai_auth = {requires_openai_auth}
     #[test]
     fn should_load_configured_environments_for_local_daemon() -> color_eyre::Result<()> {
         let target = AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: RemoteAppServerEndpoint::UnixSocket {
                 socket_path: AbsolutePathBuf::relative_to_current_dir("codex.sock")?,
             },
@@ -3069,6 +3094,7 @@ requires_openai_auth = {requires_openai_auth}
         let config = build_config(&temp_dir).await?;
         let cwd = temp_dir.path().join("project");
         let target = AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: RemoteAppServerEndpoint::UnixSocket {
                 socket_path: AbsolutePathBuf::relative_to_current_dir("codex.sock")?,
             },
@@ -3405,6 +3431,7 @@ requires_openai_auth = {requires_openai_auth}
     -> std::io::Result<()> {
         let temp_dir = TempDir::new()?;
         let target = AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: RemoteAppServerEndpoint::UnixSocket {
                 socket_path: AbsolutePathBuf::relative_to_current_dir("codex.sock")?,
             },
@@ -3481,6 +3508,7 @@ requires_openai_auth = {requires_openai_auth}
             &environment_manager
         ));
         let local_daemon = AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: RemoteAppServerEndpoint::UnixSocket {
                 socket_path: AbsolutePathBuf::relative_to_current_dir("codex.sock")?,
             },
diff --git a/codex-rs/tui/src/session_start_tests.rs b/codex-rs/tui/src/session_start_tests.rs
index c05839714b..0872a254a7 100644
--- a/codex-rs/tui/src/session_start_tests.rs
+++ b/codex-rs/tui/src/session_start_tests.rs
@@ -67,6 +67,7 @@ async fn archived_session_requires_confirmation_before_resume_or_fork() -> Resul
         let endpoint = crate::resolve_remote_addr("ws://127.0.0.1:4500")?;
         for server_target in [
             crate::AppServerTarget::LocalDaemon {
+                allow_embedded_fallback: true,
                 endpoint: endpoint.clone(),
             },
             crate::AppServerTarget::Remote { endpoint },
diff --git a/codex-rs/tui/src/snapshots/codex_tui__daemon_startup_tests__daemon_exclusion_warning.snap b/codex-rs/tui/src/snapshots/codex_tui__daemon_startup_tests__daemon_exclusion_warning.snap
new file mode 100644
index 0000000000..0dce819cdf
--- /dev/null
+++ b/codex-rs/tui/src/snapshots/codex_tui__daemon_startup_tests__daemon_exclusion_warning.snap
@@ -0,0 +1,6 @@
+---
+source: tui/src/daemon_startup_tests.rs
+expression: text
+---
+⚠ Running without the shared background server: --strict-config requires
+  embedded mode.
diff --git a/codex-rs/tui/src/startup_orchestration.rs b/codex-rs/tui/src/startup_orchestration.rs
index 82e9eba18d..b138dd0d92 100644
--- a/codex-rs/tui/src/startup_orchestration.rs
+++ b/codex-rs/tui/src/startup_orchestration.rs
@@ -155,7 +155,7 @@ pub(super) async fn run_main_inner(
         .await;
     }
 
-    let daemon_exclusion = daemon_startup::exclusion(
+    let mut daemon_exclusion = daemon_startup::exclusion(
         &cli,
         &cli_kv_overrides,
         &launch_loader_overrides,
@@ -202,7 +202,7 @@ pub(super) async fn run_main_inner(
     } else {
         None
     };
-    let app_server_target = app_server_target_for_launch(
+    let mut app_server_target = app_server_target_for_launch(
         explicit_remote_endpoint,
         default_daemon,
         reuse_implicit_local_daemon,
@@ -384,6 +384,54 @@ pub(super) async fn run_main_inner(
             strict_config,
         ))
         .await?;
+    let auto_start_daemon = config.features.enabled(Feature::DaemonAutoStart)
+        && !cli.agents_overview
+        && !cli.no_daemon
+        && !app_server_target.uses_remote_workspace();
+    if auto_start_daemon
+        && daemon_exclusion.is_none()
+        && should_show_bedrock_setup_wizard(
+            LoginStatus::NotAuthenticated,
+            config.model_provider.requires_openai_auth,
+            &config,
+            &AppServerTarget::Embedded,
+        )
+        && startup_draft
+            .run_until(
+                config
+                    .auth_config()
+                    .load_auth(/*enable_codex_api_key_env*/ false),
+            )
+            .await?
+            .ok()
+            .flatten()
+            .is_none()
+    {
+        // The Bedrock wizard configures its provider through the embedded server.
+        daemon_exclusion = Some("Bedrock sign-in");
+        app_server_target = AppServerTarget::Embedded;
+    }
+    if auto_start_daemon && daemon_exclusion.is_none() {
+        startup_draft.flush_pending_events().await?;
+        let output = startup_draft
+            .tui_mut()
+            .with_restored(|| async {
+                // Package installation may print progress; keep ordinary Ctrl+C handling.
+                crossterm::terminal::disable_raw_mode()?;
+                codex_app_server_daemon::run(codex_app_server_daemon::LifecycleCommand::Start)
+                    .await
+                    .map_err(|err| {
+                        std::io::Error::other(format!("{err:#}\n{}", daemon_startup::FAILURE_HINT))
+                    })
+            })
+            .await?;
+        app_server_target = AppServerTarget::LocalDaemon {
+            endpoint: RemoteAppServerEndpoint::UnixSocket {
+                socket_path: AbsolutePathBuf::from_absolute_path_checked(output.socket_path)?,
+            },
+            allow_embedded_fallback: false,
+        };
+    }
     startup_draft.apply_config(&config);
 
     let mut cloud_config_bundle = if workload_identity_selected {
@@ -418,6 +466,13 @@ pub(super) async fn run_main_inner(
     } else {
         None
     };
+    let daemon_startup_warning = daemon_exclusion
+        .filter(|_| auto_start_daemon)
+        .map(|reason| {
+            format!(
+                "Running without the shared background server: {reason} requires embedded mode."
+            )
+        });
     #[cfg(target_os = "macos")]
     let local_runtime_paths = local_runtime_paths.with_allowed_symlinked_codex_home(
         codex_config::allowed_symlinked_codex_home(&config.config_layer_stack, &config.codex_home),
@@ -659,6 +714,7 @@ pub(super) async fn run_main_inner(
         state_db,
         environment_manager,
         managed_worktree.clone(),
+        daemon_startup_warning,
         startup_draft,
     )
     .await
diff --git a/codex-rs/tui/src/status/remote_connection.rs b/codex-rs/tui/src/status/remote_connection.rs
index 34bd903f2b..938c9603c5 100644
--- a/codex-rs/tui/src/status/remote_connection.rs
+++ b/codex-rs/tui/src/status/remote_connection.rs
@@ -22,7 +22,7 @@ pub(crate) fn remote_connection_status_value(
 ) -> Option<RemoteConnectionStatus> {
     let endpoint = match app_server_target {
         AppServerTarget::Embedded => return None,
-        AppServerTarget::LocalDaemon { endpoint } | AppServerTarget::Remote { endpoint } => {
+        AppServerTarget::LocalDaemon { endpoint, .. } | AppServerTarget::Remote { endpoint } => {
             endpoint
         }
     };
@@ -80,7 +80,7 @@ pub(crate) fn server_version_notice_key(
     let mut hasher = Sha256::new();
     let endpoint = match target {
         AppServerTarget::Embedded => None,
-        AppServerTarget::LocalDaemon { endpoint } | AppServerTarget::Remote { endpoint } => {
+        AppServerTarget::LocalDaemon { endpoint, .. } | AppServerTarget::Remote { endpoint } => {
             Some(endpoint)
         }
     };
@@ -189,6 +189,7 @@ mod tests {
 
         let socket_path = AbsolutePathBuf::relative_to_current_dir("codex.sock")?;
         let daemon_target = AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: RemoteAppServerEndpoint::UnixSocket {
                 socket_path: socket_path.clone(),
             },
@@ -220,6 +221,7 @@ mod tests {
             socket_path: AbsolutePathBuf::relative_to_current_dir("codex.sock")?,
         };
         let local = AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: endpoint.clone(),
         };
         let remote = AppServerTarget::Remote { endpoint };
@@ -265,6 +267,7 @@ mod tests {
             })
         };
         let local = AppServerTarget::LocalDaemon {
+            allow_embedded_fallback: true,
             endpoint: socket("/c")?,
         };
         let remote = AppServerTarget::Remote {
diff --git a/codex-rs/tui/tests/suite/focus_palette.rs b/codex-rs/tui/tests/suite/focus_palette.rs
index c65b039325..70e6a6341d 100644
--- a/codex-rs/tui/tests/suite/focus_palette.rs
+++ b/codex-rs/tui/tests/suite/focus_palette.rs
@@ -402,6 +402,12 @@ fn no_daemon_skips_startup_and_discovery() -> Result<()> {
         let workspace = tempfile::tempdir()?;
         let home = tempfile::tempdir()?;
         write_test_config(home.path(), workspace.path())?;
+        let config = home.path().join("config.toml");
+        let contents = std::fs::read_to_string(&config)?;
+        std::fs::write(
+            config,
+            format!("features.daemon_auto_start = true\n{contents}"),
+        )?;
         let socket_path = codex_app_server_client::app_server_control_socket_path(home.path())?;
         std::fs::create_dir_all(socket_path.as_path().parent().unwrap())?;
         let listener = if running {
@@ -431,6 +437,55 @@ fn no_daemon_skips_startup_and_discovery() -> Result<()> {
                 std::io::ErrorKind::WouldBlock
             );
         }
+        ensure!(
+            !String::from_utf8_lossy(&terminal.output)
+                .contains("Running without the shared background server")
+        );
     }
     Ok(())
 }
+
+#[test]
+fn auto_daemon_start_failure_exits_with_manual_fallback_hint() -> Result<()> {
+    let workspace = tempfile::tempdir()?;
+    let home = tempfile::tempdir()?;
+    write_test_config(home.path(), workspace.path())?;
+    let config = home.path().join("config.toml");
+    let contents = std::fs::read_to_string(&config)?;
+    std::fs::write(
+        config,
+        format!("features.daemon_auto_start = true\n{contents}"),
+    )?;
+    // An incomplete selected package must fail without installing a replacement.
+    std::fs::create_dir_all(home.path().join("packages/app-server-daemon/current"))?;
+    let mut terminal = PtyCodex::start(workspace.path(), home, &[])?;
+    let deadline = Instant::now() + STARTUP_TIMEOUT;
+    while Instant::now() < deadline {
+        terminal.read_output(Duration::from_millis(/*millis*/ 50))?;
+        terminal.answer_startup_queries()?;
+        if let Some(status) = terminal.child.try_wait()? {
+            ensure!(!status.success());
+            let output = String::from_utf8_lossy(&terminal.output);
+            let failure = &output[output.find("Error:").context("missing fatal error")?..];
+            let failure = codex_ansi_escape::ansi_escape(failure)
+                .to_string()
+                .replace(
+                    terminal
+                        ._codex_home
+                        .path()
+                        .canonicalize()?
+                        .to_string_lossy()
+                        .as_ref(),
+                    "[CODEX_HOME]",
+                )
+                .replace(
+                    terminal._codex_home.path().to_string_lossy().as_ref(),
+                    "[CODEX_HOME]",
+                )
+                .replace('\r', "");
+            insta::assert_snapshot!("daemon_auto_start_failure", failure.trim());
+            return Ok(());
+        }
+    }
+    bail!("auto-start did not fail: {}", terminal.screen_contents())
+}
diff --git a/codex-rs/tui/tests/suite/snapshots/all__suite__focus_palette__daemon_auto_start_failure.snap b/codex-rs/tui/tests/suite/snapshots/all__suite__focus_palette__daemon_auto_start_failure.snap
new file mode 100644
index 0000000000..0d40a84782
--- /dev/null
+++ b/codex-rs/tui/tests/suite/snapshots/all__suite__focus_palette__daemon_auto_start_failure.snap
@@ -0,0 +1,7 @@
+---
+source: tui/tests/suite/focus_palette.rs
+assertion_line: 484
+expression: failure.trim()
+---
+Error: daemon executable not found at [CODEX_HOME]/packages/app-server-daemon/current/bin/codex; repair the existing installation, or run `codex app-server daemon start` to install a missing daemon
+To work without the background server, rerun the same command with --no-daemon (including resume or fork and its arguments).