Align message-board tools with the multi-agent namespace (#47028)

## Why

Message-board tools hardcoded the `collaboration` namespace and used a different namespace description from the multi-agent tools. This ignored custom namespace configuration and caused conflicts under strict tool collision checking.

## What changed

- Use `multi_agent_v2.tool_namespace` and the shared multi-agent namespace description for message-board tools, resolving the namespace at runtime startup.
- Support unnamespaced tool specifications when no namespace is supplied.
- Remove hardcoded `collaboration` prefixes from message-board notifications.

## Testing

Add app-server integration coverage for the default `collaboration` namespace and a configured `agents` namespace with strict collision checking enabled. Verify that both tool families are advertised together and that `get_channels` executes through the installed extension.

GitOrigin-RevId: fef7be51ea2a84bbdb6d3491606db442ed4e6ea3

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

@@ -0,0 +1,98 @@
+//! Board tools share MAv2 namespace metadata through the production installation path.
+
+use anyhow::Context;
+use app_test_support::MockResponsesConfig;
+use app_test_support::TestAppServer;
+use codex_app_server_protocol::ThreadStartParams;
+use codex_app_server_protocol::TurnStartParams;
+use codex_app_server_protocol::TurnStartResponse;
+use codex_app_server_protocol::UserInput;
+use codex_features::Feature;
+use core_test_support::responses;
+use pretty_assertions::assert_eq;
+use serde_json::Value;
+use serde_json::json;
+use tempfile::TempDir;
+use tokio::time::Duration;
+use tokio::time::timeout;
+
+#[test_case::test_case(None, "collaboration"; "default_namespace")]
+#[test_case::test_case(Some("agents"), "agents"; "configured_namespace")]
+#[tokio::test]
+async fn board_tools_share_multi_agent_namespace(
+    configured_namespace: Option<&str>,
+    namespace: &str,
+) -> anyhow::Result<()> {
+    let server = responses::start_mock_server().await;
+    let mock = responses::mount_sse_sequence(
+        &server,
+        vec![
+            responses::sse(vec![
+                responses::ev_function_call_with_namespace(
+                    "list-channels",
+                    namespace,
+                    "get_channels",
+                    "{}",
+                ),
+                responses::ev_completed("response-1"),
+            ]),
+            responses::sse(vec![
+                responses::ev_assistant_message("done", "Done."),
+                responses::ev_completed("response-2"),
+            ]),
+        ],
+    )
+    .await;
+    let codex_home = TempDir::new()?;
+    let namespace_config = configured_namespace
+        .map(|name| format!("tool_namespace = {name:?}"))
+        .unwrap_or_default();
+    MockResponsesConfig::new(&server.uri())
+        .enable_feature(Feature::AgentMessageBoard)
+        .disable_feature(Feature::CodeMode)
+        .disable_feature(Feature::CodeModeOnly)
+        .with_extra_config(&format!(
+            "[features.multi_agent_v2]\nenabled = true\n{namespace_config}\n\
+             [features.tool_registry]\nerror_on_tool_collisions = true"
+        ))
+        .write(codex_home.path())?;
+    let mut app = TestAppServer::builder()
+        .with_codex_home(codex_home.path())
+        .build_initialized()
+        .await?;
+    let thread = app.start_thread(ThreadStartParams::default()).await?.thread;
+    let request = app
+        .send_turn_start_request(TurnStartParams {
+            thread_id: thread.id,
+            input: vec![UserInput::Text {
+                text: "List the shared board channels.".into(),
+                text_elements: Vec::new(),
+            }],
+            ..Default::default()
+        })
+        .await?;
+    let _: TurnStartResponse = app.read_response(request).await?;
+    timeout(
+        Duration::from_secs(60),
+        app.read_stream_until_notification_message("turn/completed"),
+    )
+    .await??;
+
+    let requests = mock.requests();
+    assert_eq!(requests.len(), 2);
+    // Strict collision checking rejects different descriptions before sampling.
+    // Both tool families must also be advertised under the configured name.
+    for name in ["spawn_agent", "get_channels", "post"] {
+        assert!(requests[0].tool_by_name(namespace, name).is_some());
+    }
+    let result: Value = serde_json::from_str(
+        &requests[1]
+            .function_call_output_text("list-channels")
+            .context("board tool must execute through the installed extension")?,
+    )?;
+    assert_eq!(
+        result,
+        json!({"results": [], "n_returned": 0, "has_more": false, "next_cursor": null})
+    );
+    Ok(())
+}

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

@@ -2,6 +2,7 @@ mod account;
 #[path = "account_system_proxy_tests.rs"]
 mod account_system_proxy;
 mod account_thread_usage;
+mod agent_message_board;
 mod analytics;
 mod app_installed;
 mod app_list;