fix: include rollout_path in NewConversationResponse (#3352)

Adding the `rollout_path` to the `NewConversationResponse` makes it so a
client can perform subsequent operations on a `(ConversationId,
PathBuf)` pair. #3353 will introduce support for `ArchiveConversation`.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/3352).
* #3353
* __->__ #3352

codex-rs/Cargo.lock

@@ -830,6 +830,7 @@ dependencies = [
  "strum 0.27.2",
  "strum_macros 0.27.2",
  "sys-locale",
+ "tempfile",
  "tracing",
  "ts-rs",
  "uuid",

codex-rs/core/src/codex.rs

@@ -416,6 +416,7 @@ impl Session {
             error!("failed to initialize rollout recorder: {e:#}");
             anyhow::anyhow!("failed to initialize rollout recorder: {e:#}")
         })?;
+        let rollout_path = rollout_recorder.rollout_path.clone();
         // Create the mutable state for the Session.
         let state = State {
             history: ConversationHistory::new(),
@@ -509,6 +510,7 @@ impl Session {
                 history_log_id,
                 history_entry_count,
                 initial_messages,
+                rollout_path,
             }),
         })
         .chain(post_session_configured_error_events.into_iter());

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

@@ -72,6 +72,7 @@ pub struct SavedSession {
 #[derive(Clone)]
 pub struct RolloutRecorder {
     tx: Sender<RolloutCmd>,
+    pub(crate) rollout_path: PathBuf,
 }
 
 #[derive(Clone)]
@@ -119,13 +120,14 @@ impl RolloutRecorder {
     /// cannot be created or the rollout file cannot be opened we return the
     /// error so the caller can decide whether to disable persistence.
     pub async fn new(config: &Config, params: RolloutRecorderParams) -> std::io::Result<Self> {
-        let (file, meta) = match params {
+        let (file, rollout_path, meta) = match params {
             RolloutRecorderParams::Create {
                 conversation_id,
                 instructions,
             } => {
                 let LogFileInfo {
                     file,
+                    path,
                     conversation_id: session_id,
                     timestamp,
                 } = create_log_file(config, conversation_id)?;
@@ -140,6 +142,7 @@ impl RolloutRecorder {
 
                 (
                     tokio::fs::File::from_std(file),
+                    path,
                     Some(SessionMeta {
                         timestamp,
                         id: session_id,
@@ -150,8 +153,9 @@ impl RolloutRecorder {
             RolloutRecorderParams::Resume { path } => (
                 tokio::fs::OpenOptions::new()
                     .append(true)
-                    .open(path)
+                    .open(&path)
                     .await?,
+                path,
                 None,
             ),
         };
@@ -169,7 +173,7 @@ impl RolloutRecorder {
         // driver instead of blocking the runtime.
         tokio::task::spawn(rollout_writer(file, rx, meta, cwd));
 
-        Ok(Self { tx })
+        Ok(Self { tx, rollout_path })
     }
 
     pub(crate) async fn record_items(&self, items: &[ResponseItem]) -> std::io::Result<()> {
@@ -289,6 +293,9 @@ struct LogFileInfo {
     /// Opened file handle to the rollout file.
     file: File,
 
+    /// Full path to the rollout file.
+    path: PathBuf,
+
     /// Session ID (also embedded in filename).
     conversation_id: ConversationId,
 
@@ -328,6 +335,7 @@ fn create_log_file(
 
     Ok(LogFileInfo {
         file,
+        path,
         conversation_id,
         timestamp,
     })

codex-rs/exec/src/event_processor_with_human_output.rs

@@ -523,6 +523,7 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                     history_log_id: _,
                     history_entry_count: _,
                     initial_messages: _,
+                    rollout_path: _,
                 } = session_configured_event;
 
                 ts_println!(

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

@@ -528,6 +528,7 @@ impl CodexMessageProcessor {
                 let response = NewConversationResponse {
                     conversation_id,
                     model: session_configured.model,
+                    rollout_path: session_configured.rollout_path,
                 };
                 self.outgoing.send_response(request_id, response).await;
             }

codex-rs/mcp-server/src/outgoing_message.rs

@@ -262,6 +262,7 @@ mod tests {
     use codex_protocol::mcp_protocol::LoginChatGptCompleteNotification;
     use pretty_assertions::assert_eq;
     use serde_json::json;
+    use tempfile::NamedTempFile;
     use uuid::Uuid;
 
     use super::*;
@@ -272,6 +273,7 @@ mod tests {
         let outgoing_message_sender = OutgoingMessageSender::new(outgoing_tx);
 
         let conversation_id = ConversationId::new();
+        let rollout_file = NamedTempFile::new().unwrap();
         let event = Event {
             id: "1".to_string(),
             msg: EventMsg::SessionConfigured(SessionConfiguredEvent {
@@ -280,6 +282,7 @@ mod tests {
                 history_log_id: 1,
                 history_entry_count: 1000,
                 initial_messages: None,
+                rollout_path: rollout_file.path().to_path_buf(),
             }),
         };
 
@@ -305,12 +308,14 @@ mod tests {
         let outgoing_message_sender = OutgoingMessageSender::new(outgoing_tx);
 
         let conversation_id = ConversationId::new();
+        let rollout_file = NamedTempFile::new().unwrap();
         let session_configured_event = SessionConfiguredEvent {
             session_id: conversation_id,
             model: "gpt-4o".to_string(),
             history_log_id: 1,
             history_entry_count: 1000,
             initial_messages: None,
+            rollout_path: rollout_file.path().to_path_buf(),
         };
         let event = Event {
             id: "1".to_string(),
@@ -340,6 +345,7 @@ mod tests {
                 "history_log_id": session_configured_event.history_log_id,
                 "history_entry_count": session_configured_event.history_entry_count,
                 "type": "session_configured",
+                "rollout_path": rollout_file.path().to_path_buf(),
             }
         });
         assert_eq!(params.unwrap(), expected_params);

codex-rs/mcp-server/tests/suite/codex_message_processor_flow.rs

@@ -90,6 +90,7 @@ async fn test_codex_jsonrpc_conversation_flow() {
     let NewConversationResponse {
         conversation_id,
         model,
+        rollout_path: _,
     } = new_conv_resp;
     assert_eq!(model, "mock-model");
 

codex-rs/mcp-server/tests/suite/create_conversation.rs

@@ -59,6 +59,7 @@ async fn test_conversation_create_and_send_message_ok() {
     let NewConversationResponse {
         conversation_id,
         model,
+        rollout_path: _,
     } = to_response::<NewConversationResponse>(new_conv_resp)
         .expect("deserialize newConversation response");
     assert_eq!(model, "o3");

codex-rs/protocol/Cargo.toml

@@ -28,6 +28,7 @@ uuid = { version = "1", features = ["serde", "v4"] }
 
 [dev-dependencies]
 pretty_assertions = "1.4.1"
+tempfile = "3"
 
 [package.metadata.cargo-shear]
 # Required because the not imported as strum_macros in non-nightly builds.

codex-rs/protocol/src/mcp_protocol.rs

@@ -203,6 +203,7 @@ pub struct NewConversationParams {
 pub struct NewConversationResponse {
     pub conversation_id: ConversationId,
     pub model: String,
+    pub rollout_path: PathBuf,
 }
 
 #[derive(Serialize, Deserialize, Debug, Clone, TS)]

codex-rs/protocol/src/protocol.rs

@@ -958,6 +958,8 @@ pub struct SessionConfiguredEvent {
     /// When present, UIs can use these to seed the history.
     #[serde(skip_serializing_if = "Option::is_none")]
     pub initial_messages: Option<Vec<EventMsg>>,
+
+    pub rollout_path: PathBuf,
 }
 
 /// User's decision in response to an ExecApprovalRequest.
@@ -1020,12 +1022,15 @@ pub enum TurnAbortReason {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use serde_json::json;
+    use tempfile::NamedTempFile;
 
     /// Serialize Event to verify that its JSON representation has the expected
     /// amount of nesting.
     #[test]
     fn serialize_event() {
         let conversation_id = ConversationId(uuid::uuid!("67e55044-10b1-426f-9247-bb680e5fe0c8"));
+        let rollout_file = NamedTempFile::new().unwrap();
         let event = Event {
             id: "1234".to_string(),
             msg: EventMsg::SessionConfigured(SessionConfiguredEvent {
@@ -1034,13 +1039,22 @@ mod tests {
                 history_log_id: 0,
                 history_entry_count: 0,
                 initial_messages: None,
+                rollout_path: rollout_file.path().to_path_buf(),
             }),
         };
-        let serialized = serde_json::to_string(&event).unwrap();
+
-        assert_eq!(
+        let expected = json!({
-            serialized,
+            "id": "1234",
-            r#"{"id":"1234","msg":{"type":"session_configured","session_id":"67e55044-10b1-426f-9247-bb680e5fe0c8","model":"codex-mini-latest","history_log_id":0,"history_entry_count":0}}"#
+            "msg": {
-        );
+                "type": "session_configured",
+                "session_id": "67e55044-10b1-426f-9247-bb680e5fe0c8",
+                "model": "codex-mini-latest",
+                "history_log_id": 0,
+                "history_entry_count": 0,
+                "rollout_path": format!("{}", rollout_file.path().display()),
+            }
+        });
+        assert_eq!(expected, serde_json::to_value(&event).unwrap());
     }
 
     #[test]

codex-rs/tui/src/chatwidget/tests.rs

@@ -35,6 +35,7 @@ use std::fs::File;
 use std::io::BufRead;
 use std::io::BufReader;
 use std::path::PathBuf;
+use tempfile::NamedTempFile;
 use tokio::sync::mpsc::unbounded_channel;
 
 fn test_config() -> Config {
@@ -133,7 +134,7 @@ fn resumed_initial_messages_render_history() {
     let (mut chat, mut rx, _ops) = make_chatwidget_manual();
 
     let conversation_id = ConversationId::new();
-
+    let rollout_file = NamedTempFile::new().unwrap();
     let configured = codex_core::protocol::SessionConfiguredEvent {
         session_id: conversation_id,
         model: "test-model".to_string(),
@@ -148,6 +149,7 @@ fn resumed_initial_messages_render_history() {
                 message: "assistant reply".to_string(),
             }),
         ]),
+        rollout_path: rollout_file.path().to_path_buf(),
     };
 
     chat.handle_codex_event(Event {

codex-rs/tui/src/history_cell.rs

@@ -605,6 +605,7 @@ pub(crate) fn new_session_info(
         history_log_id: _,
         history_entry_count: _,
         initial_messages: _,
+        rollout_path: _,
     } = event;
     if is_first_event {
         let cwd_str = match relativize_to_home(&config.cwd) {

codex-rs/tui/tests/fixtures/binary-size-log.jsonl

@@ -34,7 +34,7 @@
 {"ts":"2025-08-09T15:51:04.829Z","dir":"to_tui","kind":"app_event","variant":"RequestRedraw"}
 {"ts":"2025-08-09T15:51:04.829Z","dir":"to_tui","kind":"log_line","line":"[INFO codex_core::codex] resume_path: None"}
 {"ts":"2025-08-09T15:51:04.830Z","dir":"to_tui","kind":"app_event","variant":"Redraw"}
-{"ts":"2025-08-09T15:51:04.856Z","dir":"to_tui","kind":"codex_event","payload":{"id":"0","msg":{"type":"session_configured","session_id":"d126e3d0-80ed-480a-be8c-09d97ff602cf","model":"gpt-5","history_log_id":2532619,"history_entry_count":339}}}
+{"ts":"2025-08-09T15:51:04.856Z","dir":"to_tui","kind":"codex_event","payload":{"id":"0","msg":{"type":"session_configured","session_id":"d126e3d0-80ed-480a-be8c-09d97ff602cf","model":"gpt-5","history_log_id":2532619,"history_entry_count":339,"rollout_path":"/tmp/codex-test-rollout.jsonl"}}}
 {"ts":"2025-08-09T15:51:04.856Z","dir":"to_tui","kind":"insert_history","lines":9}
 {"ts":"2025-08-09T15:51:04.857Z","dir":"to_tui","kind":"app_event","variant":"RequestRedraw"}
 {"ts":"2025-08-09T15:51:04.857Z","dir":"to_tui","kind":"app_event","variant":"RequestRedraw"}
@@ -16447,7 +16447,7 @@
 {"ts":"2025-08-09T16:06:58.083Z","dir":"to_tui","kind":"app_event","variant":"RequestRedraw"}
 {"ts":"2025-08-09T16:06:58.085Z","dir":"to_tui","kind":"app_event","variant":"Redraw"}
 {"ts":"2025-08-09T16:06:58.085Z","dir":"to_tui","kind":"log_line","line":"[INFO codex_core::codex] resume_path: None"}
-{"ts":"2025-08-09T16:06:58.136Z","dir":"to_tui","kind":"codex_event","payload":{"id":"0","msg":{"type":"session_configured","session_id":"c7df96da-daec-4fe9-aed9-3cd19b7a6192","model":"gpt-5","history_log_id":2532619,"history_entry_count":342}}}
+{"ts":"2025-08-09T16:06:58.136Z","dir":"to_tui","kind":"codex_event","payload":{"id":"0","msg":{"type":"session_configured","session_id":"c7df96da-daec-4fe9-aed9-3cd19b7a6192","model":"gpt-5","history_log_id":2532619,"history_entry_count":342,"rollout_path":"/tmp/codex-test-rollout.jsonl"}}}
 {"ts":"2025-08-09T16:06:58.136Z","dir":"to_tui","kind":"insert_history","lines":9}
 {"ts":"2025-08-09T16:06:58.136Z","dir":"to_tui","kind":"app_event","variant":"RequestRedraw"}
 {"ts":"2025-08-09T16:06:58.136Z","dir":"to_tui","kind":"app_event","variant":"RequestRedraw"}