diff --git a/codex-rs/core/src/codex.rs b/codex-rs/core/src/codex.rs
index 8401b15018..88817b655e 100644
--- a/codex-rs/core/src/codex.rs
+++ b/codex-rs/core/src/codex.rs
@@ -530,20 +530,28 @@ impl Session {
         }
     }
 
-    pub(crate) fn make_collaboration_turn_context(
+    pub(crate) async fn make_collaboration_turn_context(
         &self,
         agent: &AgentState,
         sub_id: String,
-    ) -> TurnContext {
-        Self::make_turn_context(
+    ) -> Arc<TurnContext> {
+        let per_turn_config = Self::build_per_turn_config(&agent.config);
+        let model_family = self
+            .services
+            .models_manager
+            .construct_model_family(agent.config.model.as_str(), &per_turn_config)
+            .await;
+        Arc::new(Self::make_turn_context(
             Some(Arc::clone(&self.services.auth_manager)),
             &self.services.otel_event_manager,
             agent.config.provider.clone(),
             &agent.config,
+            per_turn_config,
+            model_family,
             self.conversation_id,
             sub_id,
             agent.id,
-        )
+        ))
     }
 
     #[allow(clippy::too_many_arguments)]
@@ -1954,6 +1962,7 @@ mod handlers {
             let warning = EventMsg::Warning(WarningEvent { message });
             sess.send_event_raw(Event {
                 id: id.clone(),
+                agent_idx: Some(0),
                 msg: warning,
             })
             .await;
@@ -2537,15 +2546,19 @@ pub(crate) async fn run_collaboration_turn(
     turn_diff_tracker: SharedTurnDiffTracker,
     input: Vec<ResponseItem>,
     cancellation_token: CancellationToken,
-) -> CodexResult<Vec<ProcessedResponseItem>> {
-    run_turn(
+) -> CodexResult<(bool, Option<String>)> {
+    let TurnRunResult {
+        needs_follow_up,
+        last_agent_message,
+    } = run_turn(
         sess,
         turn_context,
         turn_diff_tracker,
         input,
         cancellation_token,
     )
-    .await
+    .await?;
+    Ok((needs_follow_up, last_agent_message))
 }
 
 /// When the model is prompted, it returns a stream of events. Some of these
diff --git a/codex-rs/core/src/tasks/collaboration.rs b/codex-rs/core/src/tasks/collaboration.rs
index cf7b03944f..21ea574d93 100644
--- a/codex-rs/core/src/tasks/collaboration.rs
+++ b/codex-rs/core/src/tasks/collaboration.rs
@@ -9,7 +9,6 @@ use tokio_util::sync::CancellationToken;
 use crate::codex::Session;
 use crate::codex::TurnContext;
 use crate::codex::run_collaboration_turn;
-use crate::response_processing::process_items;
 use crate::state::AgentId;
 use crate::state::AgentLifecycleState;
 use crate::state::TaskKind;
@@ -246,8 +245,9 @@ async fn run_agent_turns(
 
             collab.next_sub_id(target)
         };
-        let turn_context =
-            Arc::new(session.make_collaboration_turn_context(&agent_snapshot, sub_id.clone()));
+        let turn_context = session
+            .make_collaboration_turn_context(&agent_snapshot, sub_id.clone())
+            .await;
         session.register_sub_id(target, sub_id.clone()).await;
         let tracker: SharedTurnDiffTracker =
             Arc::new(tokio::sync::Mutex::new(TurnDiffTracker::new()));
@@ -259,25 +259,22 @@ async fn run_agent_turns(
             Arc::clone(&session),
             Arc::clone(&turn_context),
             tracker,
-            agent_history.get_history(),
+            agent_history.get_history_for_prompt(),
             CancellationToken::new(),
         )
         .await;
 
         let (delta_tokens, continue_running) = match run_result {
-            Ok(processed_items) => {
-                let (responses, items_to_record) =
-                    process_items(processed_items, session.as_ref(), turn_context.as_ref()).await;
+            Ok((needs_follow_up, last)) => {
                 let new_history = session.clone_history_for_agent(target).await;
                 let after_tokens = new_history.get_total_token_usage();
                 let delta_tokens = after_tokens
                     .saturating_sub(before_tokens)
                     .clamp(0, i32::MAX as i64) as i32;
-                let last = crate::codex::get_last_assistant_message_from_turn(&items_to_record);
                 {
                     let mut collab = session.collaboration_state().lock().await;
                     if let Some(agent) = collab.agent_mut(target) {
-                        if !responses.is_empty() {
+                        if needs_follow_up {
                             agent_status = AgentLifecycleState::Running;
                         } else {
                             agent_status = AgentLifecycleState::Idle {
@@ -289,7 +286,7 @@ async fn run_agent_turns(
                     }
                 }
                 last_message = last;
-                (delta_tokens, !responses.is_empty())
+                (delta_tokens, needs_follow_up)
             }
             Err(err) => {
                 {
diff --git a/codex-rs/core/src/tools/handlers/collaboration.rs b/codex-rs/core/src/tools/handlers/collaboration.rs
index b39aafd915..0b3b6aa52e 100644
--- a/codex-rs/core/src/tools/handlers/collaboration.rs
+++ b/codex-rs/core/src/tools/handlers/collaboration.rs
@@ -746,9 +746,9 @@ async fn handle_wait(
         targets
             .iter()
             .filter(|id| {
-                collab.agent(**id).is_some_and(|agent| {
-                    matches!(agent.status, AgentLifecycleState::Running)
-                })
+                collab
+                    .agent(**id)
+                    .is_some_and(|agent| matches!(agent.status, AgentLifecycleState::Running))
             })
             .map(|id| id.0)
             .collect()