[app-server] fix: ensure thread_id and turn_id are on all events (#7408)

This is an improvement for client-side developer ergonomics by
simplifying the state the client needs to keep track of.

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

@@ -1232,6 +1232,7 @@ pub struct TurnCompletedNotification {
 /// Notification that the turn-level unified diff has changed.
 /// Contains the latest aggregated diff across all file changes in the turn.
 pub struct TurnDiffUpdatedNotification {
+    pub thread_id: String,
     pub turn_id: String,
     pub diff: String,
 }
@@ -1304,6 +1305,8 @@ pub struct ItemCompletedNotification {
 #[serde(rename_all = "camelCase")]
 #[ts(export_to = "v2/")]
 pub struct AgentMessageDeltaNotification {
+    pub thread_id: String,
+    pub turn_id: String,
     pub item_id: String,
     pub delta: String,
 }
@@ -1312,6 +1315,8 @@ pub struct AgentMessageDeltaNotification {
 #[serde(rename_all = "camelCase")]
 #[ts(export_to = "v2/")]
 pub struct ReasoningSummaryTextDeltaNotification {
+    pub thread_id: String,
+    pub turn_id: String,
     pub item_id: String,
     pub delta: String,
     pub summary_index: i64,
@@ -1321,6 +1326,8 @@ pub struct ReasoningSummaryTextDeltaNotification {
 #[serde(rename_all = "camelCase")]
 #[ts(export_to = "v2/")]
 pub struct ReasoningSummaryPartAddedNotification {
+    pub thread_id: String,
+    pub turn_id: String,
     pub item_id: String,
     pub summary_index: i64,
 }
@@ -1329,6 +1336,8 @@ pub struct ReasoningSummaryPartAddedNotification {
 #[serde(rename_all = "camelCase")]
 #[ts(export_to = "v2/")]
 pub struct ReasoningTextDeltaNotification {
+    pub thread_id: String,
+    pub turn_id: String,
     pub item_id: String,
     pub delta: String,
     pub content_index: i64,
@@ -1338,6 +1347,8 @@ pub struct ReasoningTextDeltaNotification {
 #[serde(rename_all = "camelCase")]
 #[ts(export_to = "v2/")]
 pub struct CommandExecutionOutputDeltaNotification {
+    pub thread_id: String,
+    pub turn_id: String,
     pub item_id: String,
     pub delta: String,
 }
@@ -1346,6 +1357,8 @@ pub struct CommandExecutionOutputDeltaNotification {
 #[serde(rename_all = "camelCase")]
 #[ts(export_to = "v2/")]
 pub struct McpToolCallProgressNotification {
+    pub thread_id: String,
+    pub turn_id: String,
     pub item_id: String,
     pub message: String,
 }

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

@@ -260,6 +260,8 @@ pub(crate) async fn apply_bespoke_event_handling(
         }
         EventMsg::AgentMessageContentDelta(event) => {
             let notification = AgentMessageDeltaNotification {
+                thread_id: conversation_id.to_string(),
+                turn_id: event_turn_id.clone(),
                 item_id: event.item_id,
                 delta: event.delta,
             };
@@ -278,6 +280,8 @@ pub(crate) async fn apply_bespoke_event_handling(
         }
         EventMsg::ReasoningContentDelta(event) => {
             let notification = ReasoningSummaryTextDeltaNotification {
+                thread_id: conversation_id.to_string(),
+                turn_id: event_turn_id.clone(),
                 item_id: event.item_id,
                 delta: event.delta,
                 summary_index: event.summary_index,
@@ -290,6 +294,8 @@ pub(crate) async fn apply_bespoke_event_handling(
         }
         EventMsg::ReasoningRawContentDelta(event) => {
             let notification = ReasoningTextDeltaNotification {
+                thread_id: conversation_id.to_string(),
+                turn_id: event_turn_id.clone(),
                 item_id: event.item_id,
                 delta: event.delta,
                 content_index: event.content_index,
@@ -300,6 +306,8 @@ pub(crate) async fn apply_bespoke_event_handling(
         }
         EventMsg::AgentReasoningSectionBreak(event) => {
             let notification = ReasoningSummaryPartAddedNotification {
+                thread_id: conversation_id.to_string(),
+                turn_id: event_turn_id.clone(),
                 item_id: event.item_id,
                 summary_index: event.summary_index,
             };
@@ -494,6 +502,8 @@ pub(crate) async fn apply_bespoke_event_handling(
         }
         EventMsg::ExecCommandOutputDelta(exec_command_output_delta_event) => {
             let notification = CommandExecutionOutputDeltaNotification {
+                thread_id: conversation_id.to_string(),
+                turn_id: event_turn_id.clone(),
                 item_id: exec_command_output_delta_event.call_id.clone(),
                 delta: String::from_utf8_lossy(&exec_command_output_delta_event.chunk).to_string(),
             };
@@ -588,6 +598,7 @@ pub(crate) async fn apply_bespoke_event_handling(
         }
         EventMsg::TurnDiff(turn_diff_event) => {
             handle_turn_diff(
+                conversation_id,
                 &event_turn_id,
                 turn_diff_event,
                 api_version,
@@ -610,6 +621,7 @@ pub(crate) async fn apply_bespoke_event_handling(
 }
 
 async fn handle_turn_diff(
+    conversation_id: ConversationId,
     event_turn_id: &str,
     turn_diff_event: TurnDiffEvent,
     api_version: ApiVersion,
@@ -617,6 +629,7 @@ async fn handle_turn_diff(
 ) {
     if let ApiVersion::V2 = api_version {
         let notification = TurnDiffUpdatedNotification {
+            thread_id: conversation_id.to_string(),
             turn_id: event_turn_id.to_string(),
             diff: turn_diff_event.unified_diff,
         };
@@ -1774,8 +1787,10 @@ mod tests {
         let (tx, mut rx) = mpsc::channel(CHANNEL_CAPACITY);
         let outgoing = OutgoingMessageSender::new(tx);
         let unified_diff = "--- a\n+++ b\n".to_string();
+        let conversation_id = ConversationId::new();
 
         handle_turn_diff(
+            conversation_id,
             "turn-1",
             TurnDiffEvent {
                 unified_diff: unified_diff.clone(),
@@ -1793,6 +1808,7 @@ mod tests {
             OutgoingMessage::AppServerNotification(ServerNotification::TurnDiffUpdated(
                 notification,
             )) => {
+                assert_eq!(notification.thread_id, conversation_id.to_string());
                 assert_eq!(notification.turn_id, "turn-1");
                 assert_eq!(notification.diff, unified_diff);
             }
@@ -1806,8 +1822,10 @@ mod tests {
     async fn test_handle_turn_diff_is_noop_for_v1() -> Result<()> {
         let (tx, mut rx) = mpsc::channel(CHANNEL_CAPACITY);
         let outgoing = OutgoingMessageSender::new(tx);
+        let conversation_id = ConversationId::new();
 
         handle_turn_diff(
+            conversation_id,
             "turn-1",
             TurnDiffEvent {
                 unified_diff: "diff".to_string(),