core: render remote environment cwd natively (#28152)

## Why

Model-visible `<environment_context>` should match the environment of
the executor, not of the app server.

Stacked on #28146.

## What

- Keep selected environment cwd values as `PathUri` while building
environment context.
- Render cwd text using the path convention represented by the URI, with
the canonical URI as a fallback.
- Preserve compatibility with legacy `TurnContextItem.cwd` values when
reconstructing and diffing context.
- Extend the Wine-backed remote Windows test to assert that the model
sees `powershell` and `C:\windows`.

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

@@ -1621,7 +1621,7 @@ impl Session {
         &self,
         reference_context_item: Option<&TurnContextItem>,
         current_context: &TurnContext,
-    ) -> Vec<ResponseItem> {
+    ) -> CodexResult<Vec<ResponseItem>> {
         // TODO: Make context updates a pure diff of persisted previous/current TurnContextItem
         // state so replay/backtracking is deterministic. Runtime inputs that affect model-visible
         // context (shell, exec policy, feature gates, previous-turn bridge) should be persisted
@@ -1632,13 +1632,15 @@ impl Session {
         };
         let shell = self.user_shell();
         let exec_policy = self.services.exec_policy.current();
-        crate::context_manager::updates::build_settings_update_items(
-            reference_context_item,
-            previous_turn_settings.as_ref(),
-            current_context,
-            shell.as_ref(),
-            exec_policy.as_ref(),
-            self.features.enabled(Feature::Personality),
+        Ok(
+            crate::context_manager::updates::build_settings_update_items(
+                reference_context_item,
+                previous_turn_settings.as_ref(),
+                current_context,
+                shell.as_ref(),
+                exec_policy.as_ref(),
+                self.features.enabled(Feature::Personality),
+            )?,
         )
     }
 
@@ -3186,7 +3188,7 @@ impl Session {
     pub(crate) async fn record_context_updates_and_set_reference_context_item(
         &self,
         turn_context: &TurnContext,
-    ) {
+    ) -> CodexResult<()> {
         let reference_context_item = {
             let state = self.state.lock().await;
             state.reference_context_item()
@@ -3197,7 +3199,7 @@ impl Session {
         } else {
             // Steady-state path: append only context diffs to minimize token overhead.
             self.build_settings_update_items(reference_context_item.as_ref(), turn_context)
-                .await
+                .await?
         };
         let turn_context_item = turn_context.to_turn_context_item();
         if !context_items.is_empty() {
@@ -3213,6 +3215,7 @@ impl Session {
         // context items. This keeps later runtime diffing aligned with the current turn state.
         let mut state = self.state.lock().await;
         state.set_reference_context_item(Some(turn_context_item));
+        Ok(())
     }
 
     pub(crate) async fn update_token_usage_info(

codex-rs/core/src/session/rollout_reconstruction_tests.rs

@@ -9,6 +9,7 @@ use codex_protocol::protocol::CompactedItem;
 use codex_protocol::protocol::InitialHistory;
 use codex_protocol::protocol::InterAgentCommunication;
 use codex_protocol::protocol::ResumedHistory;
+use codex_utils_path_uri::PathUri;
 use pretty_assertions::assert_eq;
 use std::path::PathBuf;
 
@@ -88,7 +89,7 @@ async fn record_initial_history_resumed_bare_turn_context_does_not_hydrate_previ
     let previous_context_item = TurnContextItem {
         turn_id: Some(turn_context.sub_id.clone()),
         #[allow(deprecated)]
-        cwd: turn_context.cwd.to_path_buf(),
+        cwd: PathUri::from_abs_path(&turn_context.cwd),
         workspace_roots: None,
         current_date: turn_context.current_date.clone(),
         timezone: turn_context.timezone.clone(),
@@ -128,7 +129,7 @@ async fn record_initial_history_resumed_hydrates_previous_turn_settings_from_lif
     let mut previous_context_item = TurnContextItem {
         turn_id: Some(turn_context.sub_id.clone()),
         #[allow(deprecated)]
-        cwd: turn_context.cwd.to_path_buf(),
+        cwd: PathUri::from_abs_path(&turn_context.cwd),
         workspace_roots: None,
         current_date: turn_context.current_date.clone(),
         timezone: turn_context.timezone.clone(),
@@ -989,7 +990,7 @@ async fn record_initial_history_resumed_turn_context_after_compaction_reestablis
     let previous_context_item = TurnContextItem {
         turn_id: Some(turn_context.sub_id.clone()),
         #[allow(deprecated)]
-        cwd: turn_context.cwd.to_path_buf(),
+        cwd: PathUri::from_abs_path(&turn_context.cwd),
         workspace_roots: None,
         current_date: turn_context.current_date.clone(),
         timezone: turn_context.timezone.clone(),
@@ -1071,7 +1072,7 @@ async fn record_initial_history_resumed_turn_context_after_compaction_reestablis
         serde_json::to_value(Some(TurnContextItem {
             turn_id: Some(turn_context.sub_id.clone()),
             #[allow(deprecated)]
-            cwd: turn_context.cwd.to_path_buf(),
+            cwd: PathUri::from_abs_path(&turn_context.cwd),
             workspace_roots: None,
             current_date: turn_context.current_date.clone(),
             timezone: turn_context.timezone.clone(),
@@ -1101,7 +1102,7 @@ async fn record_initial_history_resumed_aborted_turn_without_id_clears_active_tu
     let previous_context_item = TurnContextItem {
         turn_id: Some(turn_context.sub_id.clone()),
         #[allow(deprecated)]
-        cwd: turn_context.cwd.to_path_buf(),
+        cwd: PathUri::from_abs_path(&turn_context.cwd),
         workspace_roots: None,
         current_date: turn_context.current_date.clone(),
         timezone: turn_context.timezone.clone(),
@@ -1223,7 +1224,7 @@ async fn record_initial_history_resumed_unmatched_abort_preserves_active_turn_fo
     let current_context_item = TurnContextItem {
         turn_id: Some(current_turn_id.clone()),
         #[allow(deprecated)]
-        cwd: turn_context.cwd.to_path_buf(),
+        cwd: PathUri::from_abs_path(&turn_context.cwd),
         workspace_roots: None,
         current_date: turn_context.current_date.clone(),
         timezone: turn_context.timezone.clone(),
@@ -1343,7 +1344,7 @@ async fn record_initial_history_resumed_trailing_incomplete_turn_compaction_clea
     let previous_context_item = TurnContextItem {
         turn_id: Some(turn_context.sub_id.clone()),
         #[allow(deprecated)]
-        cwd: turn_context.cwd.to_path_buf(),
+        cwd: PathUri::from_abs_path(&turn_context.cwd),
         workspace_roots: None,
         current_date: turn_context.current_date.clone(),
         timezone: turn_context.timezone.clone(),
@@ -1506,7 +1507,7 @@ async fn record_initial_history_resumed_replaced_incomplete_compacted_turn_clear
     let previous_context_item = TurnContextItem {
         turn_id: Some(turn_context.sub_id.clone()),
         #[allow(deprecated)]
-        cwd: turn_context.cwd.to_path_buf(),
+        cwd: PathUri::from_abs_path(&turn_context.cwd),
         workspace_roots: None,
         current_date: turn_context.current_date.clone(),
         timezone: turn_context.timezone.clone(),

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

@@ -1874,7 +1874,8 @@ async fn resumed_history_injects_initial_context_on_first_context_update_only()
 
     session
         .record_context_updates_and_set_reference_context_item(&turn_context)
-        .await;
+        .await
+        .expect("context updates should hydrate");
     let initial_context = session.build_initial_context(&turn_context).await;
     expected.extend(initial_context);
     let history_after_seed = session.clone_history().await;
@@ -1882,7 +1883,8 @@ async fn resumed_history_injects_initial_context_on_first_context_update_only()
 
     session
         .record_context_updates_and_set_reference_context_item(&turn_context)
-        .await;
+        .await
+        .expect("context updates should hydrate");
     let history_after_second_seed = session.clone_history().await;
     assert_eq!(
         history_after_seed.raw_items(),
@@ -2673,7 +2675,7 @@ async fn record_initial_history_forked_hydrates_previous_turn_settings() {
     let previous_context_item = TurnContextItem {
         turn_id: Some(turn_context.sub_id.clone()),
         #[allow(deprecated)]
-        cwd: turn_context.cwd.to_path_buf(),
+        cwd: PathUri::from_abs_path(&turn_context.cwd),
         workspace_roots: None,
         current_date: turn_context.current_date.clone(),
         timezone: turn_context.timezone.clone(),
@@ -7290,7 +7292,8 @@ async fn build_settings_update_items_emits_environment_item_for_network_changes(
     let reference_context_item = previous_context.to_turn_context_item();
     let update_items = session
         .build_settings_update_items(Some(&reference_context_item), &current_context)
-        .await;
+        .await
+        .expect("settings updates should hydrate");
 
     let environment_update = user_input_texts(&update_items)
         .into_iter()
@@ -7360,7 +7363,8 @@ async fn build_settings_update_items_emits_environment_item_for_time_changes() {
     let reference_context_item = previous_context.to_turn_context_item();
     let update_items = session
         .build_settings_update_items(Some(&reference_context_item), &current_context)
-        .await;
+        .await
+        .expect("settings updates should hydrate");
 
     let environment_update = user_input_texts(&update_items)
         .into_iter()
@@ -7388,7 +7392,8 @@ async fn build_settings_update_items_omits_environment_item_when_disabled() {
     let reference_context_item = previous_context.to_turn_context_item();
     let update_items = session
         .build_settings_update_items(Some(&reference_context_item), &current_context)
-        .await;
+        .await
+        .expect("settings updates should hydrate");
 
     let user_texts = user_input_texts(&update_items);
     assert!(
@@ -7416,7 +7421,8 @@ async fn build_settings_update_items_emits_realtime_start_when_session_becomes_l
             Some(&previous_context.to_turn_context_item()),
             &current_context,
         )
-        .await;
+        .await
+        .expect("settings updates should hydrate");
 
     let developer_texts = developer_input_texts(&update_items);
     assert!(
@@ -7444,7 +7450,8 @@ async fn build_settings_update_items_emits_realtime_end_when_session_stops_being
             Some(&previous_context.to_turn_context_item()),
             &current_context,
         )
-        .await;
+        .await
+        .expect("settings updates should hydrate");
 
     let developer_texts = developer_input_texts(&update_items);
     assert!(
@@ -7478,7 +7485,8 @@ async fn build_settings_update_items_uses_previous_turn_settings_for_realtime_en
         .await;
     let update_items = session
         .build_settings_update_items(Some(&previous_context_item), &current_context)
-        .await;
+        .await
+        .expect("settings updates should hydrate");
 
     let developer_texts = developer_input_texts(&update_items);
     assert!(
@@ -8130,6 +8138,21 @@ async fn turn_context_item_uses_turn_context_comp_hash_snapshot() {
     );
 }
 
+#[tokio::test]
+async fn turn_context_item_stores_primary_environment_cwd_uri() {
+    let (_session, mut turn_context) = make_session_and_context().await;
+    let environment = turn_context.environments.turn_environments[0].clone();
+    let cwd = PathUri::parse("file:///C:/windows").expect("Windows cwd URI");
+    turn_context.environments.turn_environments[0] = TurnEnvironment::new(
+        "remote".to_string(),
+        environment.environment,
+        cwd.clone(),
+        environment.shell,
+    );
+
+    assert_eq!(turn_context.to_turn_context_item().cwd, cwd);
+}
+
 #[tokio::test]
 async fn turn_context_item_omits_legacy_equivalent_file_system_sandbox_policy() {
     let (_session, turn_context) = make_session_and_context().await;
@@ -8171,7 +8194,8 @@ async fn record_context_updates_and_set_reference_context_item_injects_full_cont
     let (session, turn_context) = make_session_and_context().await;
     session
         .record_context_updates_and_set_reference_context_item(&turn_context)
-        .await;
+        .await
+        .expect("context updates should hydrate");
     let history = session.clone_history().await;
     let initial_context = session.build_initial_context(&turn_context).await;
     assert_eq!(history.raw_items().to_vec(), initial_context);
@@ -8202,7 +8226,8 @@ async fn record_context_updates_and_set_reference_context_item_reinjects_full_co
         .await;
     session
         .record_context_updates_and_set_reference_context_item(&turn_context)
-        .await;
+        .await
+        .expect("context updates should hydrate");
     {
         let mut state = session.state.lock().await;
         state.set_reference_context_item(/*item*/ None);
@@ -8216,7 +8241,8 @@ async fn record_context_updates_and_set_reference_context_item_reinjects_full_co
 
     session
         .record_context_updates_and_set_reference_context_item(&turn_context)
-        .await;
+        .await
+        .expect("context updates should hydrate");
 
     let history = session.clone_history().await;
     let mut expected_history = vec![compacted_summary];
@@ -8246,12 +8272,14 @@ async fn record_context_updates_and_set_reference_context_item_persists_baseline
 
     let update_items = session
         .build_settings_update_items(Some(&previous_context_item), &turn_context)
-        .await;
+        .await
+        .expect("settings updates should hydrate");
     assert_eq!(update_items, Vec::new());
 
     session
         .record_context_updates_and_set_reference_context_item(&turn_context)
-        .await;
+        .await
+        .expect("context updates should hydrate");
 
     assert_eq!(
         session.clone_history().await.raw_items().to_vec(),
@@ -8298,7 +8326,8 @@ async fn record_context_updates_and_set_reference_context_item_persists_split_fi
 
     session
         .record_context_updates_and_set_reference_context_item(&turn_context)
-        .await;
+        .await
+        .expect("context updates should hydrate");
     session.ensure_rollout_materialized().await;
     session.flush_rollout().await.expect("rollout should flush");
 
@@ -8382,7 +8411,8 @@ async fn record_context_updates_and_set_reference_context_item_persists_full_rei
         .await;
     session
         .record_context_updates_and_set_reference_context_item(&turn_context)
-        .await;
+        .await
+        .expect("context updates should hydrate");
     session.ensure_rollout_materialized().await;
     session.flush_rollout().await.expect("rollout should flush");
 

codex-rs/core/src/session/turn.rs

@@ -159,8 +159,16 @@ pub(crate) async fn run_turn(
         return None;
     }
 
-    sess.record_context_updates_and_set_reference_context_item(turn_context.as_ref())
-        .await;
+    if let Err(err) = sess
+        .record_context_updates_and_set_reference_context_item(turn_context.as_ref())
+        .await
+    {
+        let error = err.to_codex_protocol_error();
+        sess.emit_turn_error_lifecycle(turn_context.as_ref(), error.clone())
+            .await;
+        error!(%err, "failed to hydrate persisted turn context");
+        return None;
+    }
 
     let (injection_items, explicitly_enabled_connectors) =
         build_skills_and_plugins(&sess, turn_context.as_ref(), &input, &cancellation_token).await?;

codex-rs/core/src/session/turn_context.rs

@@ -396,10 +396,17 @@ impl TurnContext {
 
     pub(crate) fn to_turn_context_item(&self) -> TurnContextItem {
         let workspace_roots = self.config.effective_workspace_roots();
+        let cwd = self
+            .environments
+            .primary()
+            .map(|environment| environment.cwd().clone())
+            .unwrap_or_else(|| {
+                #[allow(deprecated)]
+                PathUri::from_abs_path(&self.cwd)
+            });
         TurnContextItem {
             turn_id: Some(self.sub_id.clone()),
-            #[allow(deprecated)]
-            cwd: self.cwd.to_path_buf(),
+            cwd,
             workspace_roots: (!workspace_roots.is_empty()).then_some(workspace_roots),
             current_date: self.current_date.clone(),
             timezone: self.timezone.clone(),