Expose collaboration presets (#9421)

Expose collaboration presets for clients

---------

Co-authored-by: Josh McKinney <joshka@openai.com>

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

@@ -0,0 +1,85 @@
+//! 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, collaborate, and execute modes with their default model and reasoning
+//! effort settings, which keeps the API contract visible in one place.
+
+use std::time::Duration;
+
+use anyhow::Result;
+use app_test_support::McpProcess;
+use app_test_support::to_response;
+use codex_app_server_protocol::CollaborationModeListParams;
+use codex_app_server_protocol::CollaborationModeListResponse;
+use codex_app_server_protocol::JSONRPCResponse;
+use codex_app_server_protocol::RequestId;
+use codex_protocol::config_types::CollaborationMode;
+use codex_protocol::config_types::Settings;
+use codex_protocol::openai_models::ReasoningEffort;
+use pretty_assertions::assert_eq;
+use tempfile::TempDir;
+use tokio::time::timeout;
+
+const DEFAULT_TIMEOUT: Duration = Duration::from_secs(10);
+
+/// Confirms the server returns the default collaboration mode presets in a stable order.
+#[tokio::test]
+async fn list_collaboration_modes_returns_presets() -> Result<()> {
+    let codex_home = TempDir::new()?;
+    let mut mcp = McpProcess::new(codex_home.path()).await?;
+
+    timeout(DEFAULT_TIMEOUT, mcp.initialize()).await??;
+
+    let request_id = mcp
+        .send_list_collaboration_modes_request(CollaborationModeListParams {})
+        .await?;
+
+    let response: JSONRPCResponse = timeout(
+        DEFAULT_TIMEOUT,
+        mcp.read_stream_until_response_message(RequestId::Integer(request_id)),
+    )
+    .await??;
+
+    let CollaborationModeListResponse { data: items } =
+        to_response::<CollaborationModeListResponse>(response)?;
+
+    let expected = vec![plan_preset(), collaborate_preset(), execute_preset()];
+    assert_eq!(expected, items);
+    Ok(())
+}
+
+/// Builds the plan preset that the list response is expected to return.
+///
+/// If the defaults change in the app server, this helper should be updated alongside the
+/// contract, or the test will fail in ways that imply a regression in the API.
+fn plan_preset() -> CollaborationMode {
+    CollaborationMode::Plan(Settings {
+        model: "gpt-5.2-codex".to_string(),
+        reasoning_effort: Some(ReasoningEffort::Medium),
+        developer_instructions: None,
+    })
+}
+
+/// Builds the collaborate preset that the list response is expected to return.
+///
+/// The helper keeps the expected model and reasoning defaults co-located with the test
+/// so that mismatches point directly at the API contract being exercised.
+fn collaborate_preset() -> CollaborationMode {
+    CollaborationMode::Collaborate(Settings {
+        model: "gpt-5.2-codex".to_string(),
+        reasoning_effort: Some(ReasoningEffort::Medium),
+        developer_instructions: None,
+    })
+}
+
+/// Builds the execute preset that the list response is expected to return.
+///
+/// The execute preset uses a different reasoning effort to capture the higher-effort
+/// execution contract the server currently exposes.
+fn execute_preset() -> CollaborationMode {
+    CollaborationMode::Execute(Settings {
+        model: "gpt-5.2-codex".to_string(),
+        reasoning_effort: Some(ReasoningEffort::XHigh),
+        developer_instructions: None,
+    })
+}

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

@@ -1,5 +1,6 @@
 mod account;
 mod analytics;
+mod collaboration_mode_list;
 mod config_rpc;
 mod initialize;
 mod model_list;