Reduce the surface of collaboration modes (#20149)

Collaboration modes were slightly invasive both into ThreadManager
construction and ModelProvider

codex-rs/app-server/README.md

@@ -194,7 +194,7 @@ Example with notification opt-out:
 - `modelProvider/capabilities/read` — read provider-level capabilities for the currently configured model provider.
 - `experimentalFeature/list` — list feature flags with stage metadata (`beta`, `underDevelopment`, `stable`, etc.), enabled/default-enabled state, and cursor pagination. For non-beta flags, `displayName`/`description`/`announcement` are `null`.
 - `experimentalFeature/enablement/set` — patch the in-memory process-wide runtime feature enablement for the currently supported feature keys (`apps`, `memories`, `plugins`, `remote_control`, `tool_search`, `tool_suggest`, `tool_call_mcp_elicitation`). For each feature, precedence is: cloud requirements > --enable <feature_name> > config.toml > experimentalFeature/enablement/set (new) > code default.
-- `collaborationMode/list` — list available collaboration mode presets (experimental, no pagination). This response omits built-in developer instructions; clients should either pass `settings.developer_instructions: null` when setting a mode to use Codex's built-in instructions, or provide their own instructions explicitly.
+- `collaborationMode/list` — list available collaboration mode presets (experimental, no pagination). Built-in presets do not select a model; the Plan preset selects medium reasoning effort. This response omits built-in developer instructions; clients should either pass `settings.developer_instructions: null` when setting a mode to use Codex's built-in instructions, or provide their own instructions explicitly.
 - `skills/list` — list skills for one or more `cwd` values (optional `forceReload`).
 - `hooks/list` — list discovered hooks for one or more `cwd` values.
 - `marketplace/add` — add a remote plugin marketplace from an HTTP(S) Git URL, SSH Git URL, or GitHub `owner/repo` shorthand, then persist it into the user marketplace config. Returns the installed root path plus whether the marketplace was already present.

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

@@ -323,7 +323,6 @@ use codex_mcp::resolve_oauth_scopes;
 use codex_memories_write::clear_memory_roots_contents;
 use codex_model_provider::ProviderAccountError;
 use codex_model_provider::create_model_provider;
-use codex_models_manager::collaboration_mode_presets::CollaborationModesConfig;
 use codex_models_manager::collaboration_mode_presets::builtin_collaboration_mode_presets;
 use codex_protocol::ThreadId;
 use codex_protocol::config_types::CollaborationMode;
@@ -903,15 +902,13 @@ impl CodexMessageProcessor {
     fn normalize_turn_start_collaboration_mode(
         &self,
         mut collaboration_mode: CollaborationMode,
-        collaboration_modes_config: CollaborationModesConfig,
     ) -> CollaborationMode {
         if collaboration_mode.settings.developer_instructions.is_none()
-            && let Some(instructions) =
-                builtin_collaboration_mode_presets(collaboration_modes_config)
-                    .into_iter()
-                    .find(|preset| preset.mode == Some(collaboration_mode.mode))
-                    .and_then(|preset| preset.developer_instructions.flatten())
-                    .filter(|instructions| !instructions.is_empty())
+            && let Some(instructions) = builtin_collaboration_mode_presets()
+                .into_iter()
+                .find(|preset| preset.mode == Some(collaboration_mode.mode))
+                .and_then(|preset| preset.developer_instructions.flatten())
+                .filter(|instructions| !instructions.is_empty())
         {
             collaboration_mode.settings.developer_instructions = Some(instructions);
         }
@@ -6566,13 +6563,9 @@ impl CodexMessageProcessor {
                 self.track_error_response(&request_id, error, /*error_type*/ None);
             })?;
 
-            let collaboration_modes_config = CollaborationModesConfig {
-                default_mode_request_user_input: thread
-                    .enabled(Feature::DefaultModeRequestUserInput),
-            };
-            let collaboration_mode = params.collaboration_mode.map(|mode| {
-                self.normalize_turn_start_collaboration_mode(mode, collaboration_modes_config)
-            });
+            let collaboration_mode = params
+                .collaboration_mode
+                .map(|mode| self.normalize_turn_start_collaboration_mode(mode));
             let environments: Option<Vec<TurnEnvironmentSelection>> =
                 params.environments.map(|environments| {
                     environments

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

@@ -79,7 +79,6 @@ use codex_login::default_client::get_codex_user_agent;
 use codex_login::default_client::set_default_client_residency_requirement;
 use codex_login::default_client::set_default_originator;
 use codex_model_provider::create_model_provider;
-use codex_models_manager::collaboration_mode_presets::CollaborationModesConfig;
 use codex_protocol::ThreadId;
 use codex_protocol::protocol::SessionSource;
 use codex_protocol::protocol::W3cTraceContext;
@@ -290,11 +289,6 @@ impl MessageProcessor {
             config.as_ref(),
             auth_manager.clone(),
             session_source,
-            CollaborationModesConfig {
-                default_mode_request_user_input: config
-                    .features
-                    .enabled(Feature::DefaultModeRequestUserInput),
-            },
             environment_manager,
             Some(analytics_events_client.clone()),
         ));

codex-rs/app-server/tests/suite/v2/collaboration_mode_list.rs

@@ -1,8 +1,7 @@
 //! Validates that the collaboration mode list endpoint returns the expected default presets.
 //!
 //! The test drives the app server through the MCP harness and asserts that the list response
-//! includes the plan and default modes with their default model and reasoning effort
-//! settings, which keeps the API contract visible in one place.
+//! includes the plan and default modes, which keeps the API contract visible in one place.
 
 #![allow(clippy::unwrap_used)]
 

codex-rs/app-server/tests/suite/v2/turn_start.rs

@@ -969,7 +969,7 @@ async fn turn_start_accepts_collaboration_mode_override_v2() -> Result<()> {
         codex_home.path(),
         &server.uri(),
         "never",
-        &BTreeMap::from([(Feature::DefaultModeRequestUserInput, true)]),
+        &BTreeMap::default(),
     )?;
 
     let mut mcp = McpProcess::new(codex_home.path()).await?;
@@ -1029,13 +1029,15 @@ async fn turn_start_accepts_collaboration_mode_override_v2() -> Result<()> {
     let payload = request.body_json();
     assert_eq!(payload["model"].as_str(), Some("mock-model-collab"));
     let payload_text = payload.to_string();
-    assert!(payload_text.contains("The `request_user_input` tool is available in Default mode."));
+    assert!(payload_text.contains(
+        "Use the `request_user_input` tool only when it is listed in the available tools"
+    ));
 
     Ok(())
 }
 
 #[tokio::test]
-async fn turn_start_uses_thread_feature_overrides_for_collaboration_mode_instructions_v2()
+async fn turn_start_uses_thread_feature_overrides_for_request_user_input_tool_description_v2()
 -> Result<()> {
     skip_if_no_network!(Ok(()));
 
@@ -1114,7 +1116,7 @@ async fn turn_start_uses_thread_feature_overrides_for_collaboration_mode_instruc
 
     let request = response_mock.single_request();
     let payload_text = request.body_json().to_string();
-    assert!(payload_text.contains("The `request_user_input` tool is available in Default mode."));
+    assert!(payload_text.contains("This tool is only available in Default or Plan mode."));
 
     Ok(())
 }