Simplify injected message envelopes

codex-rs/core/src/codex/timer_runtime.rs

@@ -32,6 +32,7 @@ use super::EventMsg;
 use super::INITIAL_SUBMIT_ID;
 use super::Session;
 use crate::messages::MessageInvocationContext;
+use crate::messages::MessageInvocationKind;
 use crate::messages::MessagePayload;
 use crate::messages::db_message_to_thread_message;
 use crate::messages::injected_message_event;
@@ -381,11 +382,10 @@ impl Session {
                     };
                     let delivery = message.delivery;
                     let message_context = MessageInvocationContext {
+                        kind: MessageInvocationKind::External,
                         source: message.source.clone(),
-                        content: message.content.clone(),
-                        instructions: message.instructions.clone(),
-                        meta: message.meta.clone(),
-                        queued_at: message.queued_at,
+                        content: message.content,
+                        instructions: None,
                     };
                     let input_item = PendingInputItem::GeneratedMessage(GeneratedMessageInput {
                         item: message_prompt_input_item(&message_context),

codex-rs/core/src/codex_tests.rs

@@ -5067,7 +5067,8 @@ async fn generated_message_records_raw_item_and_emits_injected_event() {
         id: None,
         role: "user".to_string(),
         content: vec![ContentItem::InputText {
-            text: "<codex_message><content>hidden wrapper</content></codex_message>".to_string(),
+            text: "<external_message><content>hidden wrapper</content></external_message>"
+                .to_string(),
         }],
         end_turn: None,
         phase: None,

codex-rs/core/src/messages.rs

@@ -8,8 +8,10 @@ use serde::Deserialize;
 use serde::Serialize;
 use std::collections::BTreeMap;
 
-pub const CODEX_MESSAGE_OPEN_TAG: &str = "<codex_message>";
-pub const CODEX_MESSAGE_CLOSE_TAG: &str = "</codex_message>";
+const EXTERNAL_MESSAGE_OPEN_TAG: &str = "<external_message>";
+const EXTERNAL_MESSAGE_CLOSE_TAG: &str = "</external_message>";
+const TIMER_MESSAGE_OPEN_TAG: &str = "<timer_message>";
+const TIMER_MESSAGE_CLOSE_TAG: &str = "</timer_message>";
 
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub struct MessagePayload {
@@ -32,13 +34,18 @@ pub struct ThreadMessage {
     pub queued_at: i64,
 }
 
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub(crate) enum MessageInvocationKind {
+    External,
+    Timer { timer_id: String },
+}
+
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub(crate) struct MessageInvocationContext {
+    pub(crate) kind: MessageInvocationKind,
     pub(crate) source: String,
     pub(crate) content: String,
     pub(crate) instructions: Option<String>,
-    pub(crate) meta: BTreeMap<String, String>,
-    pub(crate) queued_at: i64,
 }
 
 pub fn validate_meta_key(key: &str) -> Result<(), String> {
@@ -81,28 +88,24 @@ pub(crate) fn injected_message_event(message: &MessageInvocationContext) -> Inje
 
 pub(crate) fn render_message_prompt(message: &MessageInvocationContext) -> String {
     let mut rendered = String::new();
-    rendered.push_str(CODEX_MESSAGE_OPEN_TAG);
-    rendered.push('\n');
-    push_tag(&mut rendered, "source", &message.source);
-    push_tag(&mut rendered, "queued_at", &message.queued_at.to_string());
-    push_block_tag(&mut rendered, "content", &message.content);
-    if let Some(instructions) = message.instructions.as_deref() {
-        push_block_tag(&mut rendered, "instructions", instructions);
-    }
-    if message.meta.is_empty() {
-        rendered.push_str("<meta />\n");
-    } else {
-        rendered.push_str("<meta>\n");
-        for (key, value) in &message.meta {
-            rendered.push_str("  <entry id=\"");
-            rendered.push_str(&xml_escape(key));
-            rendered.push_str("\">");
-            rendered.push_str(&xml_escape(value));
-            rendered.push_str("</entry>\n");
+    match &message.kind {
+        MessageInvocationKind::External => {
+            rendered.push_str(EXTERNAL_MESSAGE_OPEN_TAG);
+            rendered.push('\n');
+            push_block_tag(&mut rendered, "content", &message.content);
+            rendered.push_str(EXTERNAL_MESSAGE_CLOSE_TAG);
+        }
+        MessageInvocationKind::Timer { timer_id } => {
+            rendered.push_str(TIMER_MESSAGE_OPEN_TAG);
+            rendered.push('\n');
+            push_tag(&mut rendered, "timer_id", timer_id);
+            push_block_tag(&mut rendered, "content", &message.content);
+            if let Some(instructions) = message.instructions.as_deref() {
+                push_block_tag(&mut rendered, "instructions", instructions);
+            }
+            rendered.push_str(TIMER_MESSAGE_CLOSE_TAG);
         }
-        rendered.push_str("</meta>\n");
     }
-    rendered.push_str(CODEX_MESSAGE_CLOSE_TAG);
     rendered
 }
 
@@ -162,18 +165,34 @@ mod tests {
     use pretty_assertions::assert_eq;
 
     #[test]
-    fn renders_message_prompt_with_escaped_metadata() {
+    fn renders_external_message_prompt_with_only_content() {
         let message = MessageInvocationContext {
-            source: "timer timer-1".to_string(),
+            kind: MessageInvocationKind::External,
+            source: "external".to_string(),
             content: "run <tests>".to_string(),
             instructions: Some("stay \"brief\"".to_string()),
-            meta: BTreeMap::from([("ticket".to_string(), "ABC&123".to_string())]),
-            queued_at: 100,
         };
 
         assert_eq!(
             render_message_prompt(&message),
-            "<codex_message>\n<source>timer timer-1</source>\n<queued_at>100</queued_at>\n<content>\nrun &lt;tests&gt;\n</content>\n<instructions>\nstay &quot;brief&quot;\n</instructions>\n<meta>\n  <entry id=\"ticket\">ABC&amp;123</entry>\n</meta>\n</codex_message>"
+            "<external_message>\n<content>\nrun &lt;tests&gt;\n</content>\n</external_message>"
+        );
+    }
+
+    #[test]
+    fn renders_timer_message_prompt_with_timer_id_and_no_metadata() {
+        let message = MessageInvocationContext {
+            kind: MessageInvocationKind::Timer {
+                timer_id: "timer-1".to_string(),
+            },
+            source: "timer timer-1".to_string(),
+            content: "run <tests>".to_string(),
+            instructions: Some("stay \"brief\"".to_string()),
+        };
+
+        assert_eq!(
+            render_message_prompt(&message),
+            "<timer_message>\n<timer_id>timer-1</timer_id>\n<content>\nrun &lt;tests&gt;\n</content>\n<instructions>\nstay &quot;brief&quot;\n</instructions>\n</timer_message>"
         );
     }
 

codex-rs/core/src/timers.rs

@@ -5,6 +5,7 @@
 //! restore timers after a harness restart.
 
 use crate::messages::MessageInvocationContext;
+use crate::messages::MessageInvocationKind;
 use crate::messages::MessagePayload;
 use crate::messages::validate_meta;
 use crate::timer_trigger::TimerTrigger;
@@ -488,11 +489,12 @@ pub(crate) fn timer_message_invocation_context(
     timer: &TimerInvocationContext,
 ) -> MessageInvocationContext {
     MessageInvocationContext {
+        kind: MessageInvocationKind::Timer {
+            timer_id: timer.current_timer_id.clone(),
+        },
         source: format!("timer {}", timer.current_timer_id),
         content: timer_message_content(timer),
         instructions: timer_message_instructions(timer),
-        meta: timer.meta.clone(),
-        queued_at: timer.queued_at,
     }
 }
 
@@ -947,7 +949,7 @@ mod tests {
             ResponseInputItem::Message {
                 role: "user".to_string(),
                 content: vec![ContentItem::InputText {
-                    text: "<codex_message>\n<source>timer timer-1</source>\n<queued_at>100</queued_at>\n<content>\nTimer fired: run tests\n</content>\n<instructions>\nrun tests\n\nThis timer should keep running on its schedule after this invocation.\nDo not call delete_timer just because you completed this invocation.\nCall delete_timer with {&quot;id&quot;:&quot;timer-1&quot;} only if the user's timer message included an explicit stop condition, such as &quot;until&quot;, &quot;stop when&quot;, or &quot;while&quot;, and that condition is now satisfied.\nDo not expose scheduler internals unless they matter to the user.\n</instructions>\n<meta />\n</codex_message>".to_string(),
+                    text: "<timer_message>\n<timer_id>timer-1</timer_id>\n<content>\nTimer fired: run tests\n</content>\n<instructions>\nrun tests\n\nThis timer should keep running on its schedule after this invocation.\nDo not call delete_timer just because you completed this invocation.\nCall delete_timer with {&quot;id&quot;:&quot;timer-1&quot;} only if the user's timer message included an explicit stop condition, such as &quot;until&quot;, &quot;stop when&quot;, or &quot;while&quot;, and that condition is now satisfied.\nDo not expose scheduler internals unless they matter to the user.\n</instructions>\n</timer_message>".to_string(),
                 }],
             }
         );
@@ -969,7 +971,7 @@ mod tests {
             ResponseInputItem::Message {
                 role: "user".to_string(),
                 content: vec![ContentItem::InputText {
-                    text: "<codex_message>\n<source>timer timer-1</source>\n<queued_at>101</queued_at>\n<content>\nTimer fired: run tests once\n</content>\n<instructions>\nrun tests once\n\nuser-specific instruction\n\nThis one-shot timer has already been removed from the schedule, so you do not need to call delete_timer.\nDo not expose scheduler internals unless they matter to the user.\n</instructions>\n<meta>\n  <entry id=\"ticket\">ABC_123</entry>\n</meta>\n</codex_message>".to_string(),
+                    text: "<timer_message>\n<timer_id>timer-1</timer_id>\n<content>\nTimer fired: run tests once\n</content>\n<instructions>\nrun tests once\n\nuser-specific instruction\n\nThis one-shot timer has already been removed from the schedule, so you do not need to call delete_timer.\nDo not expose scheduler internals unless they matter to the user.\n</instructions>\n</timer_message>".to_string(),
                 }],
             }
         );

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

@@ -117,14 +117,13 @@ async fn assert_after_turn_timer_starts_and_emits_fired_event() -> Result<()> {
     let user_messages = mock.single_request().message_input_texts("user");
     let timer_messages = user_messages
         .iter()
-        .filter(|message| message.contains("<codex_message>"))
+        .filter(|message| message.contains("<timer_message>"))
         .collect::<Vec<_>>();
     assert_eq!(timer_messages.len(), 1);
     let timer_message = timer_messages[0];
-    assert!(timer_message.contains(&format!("<source>timer {}</source>", created.id)));
+    assert!(timer_message.contains(&format!("<timer_id>{}</timer_id>", created.id)));
     assert!(timer_message.contains("<content>\nTimer fired: run timer\n</content>"));
     assert!(timer_message.contains("<instructions>\nrun timer\n\nThis one-shot timer"));
-    assert!(timer_message.contains("<meta />"));
 
     Ok(())
 }