Build MCP tool runtimes before router planning (#33149)

## What changed

- Convert filtered MCP tool metadata into `CoreToolRuntime` instances before constructing the tool router.
- Pass those runtimes through the shared tool-planning path instead of maintaining separate direct and deferred MCP tool lists.
- Preserve MCP visibility, app policy filtering, and direct versus deferred exposure behavior.

GitOrigin-RevId: 67f7fbeecc2992318c859e038cd97938833911db

codex-rs/core/src/tools/router_tests.rs

@@ -4,6 +4,8 @@ use crate::config::Config;
 use crate::session::step_context::StepContext;
 use crate::session::tests::make_session_and_context;
 use crate::tools::context::ToolPayload;
+use crate::tools::handlers::McpHandler;
+use crate::tools::registry::CoreToolRuntime;
 use crate::turn_diff_tracker::TurnDiffTracker;
 use codex_extension_api::ExtensionData;
 use codex_extension_api::ExtensionRegistry;
@@ -105,21 +107,14 @@ fn extension_tool_test_registry() -> Arc<ExtensionRegistry<Config>> {
 
 #[tokio::test]
 async fn parallel_support_does_not_match_namespaced_local_tool_names() -> anyhow::Result<()> {
-    let (session, turn) = make_session_and_context().await;
+    let (_, turn) = make_session_and_context().await;
     let turn = Arc::new(turn);
     let step_context = StepContext::for_test(Arc::clone(&turn));
-    let mcp_tools = session
-        .services
-        .latest_mcp_runtime()
-        .manager()
-        .list_all_tools()
-        .await;
     let router = ToolRouter::from_context(
         step_context.as_ref(),
         ToolRouterParams {
             tool_suggest_candidates: None,
-            deferred_mcp_tools: None,
-            mcp_tools: Some(mcp_tools),
+            tool_runtimes: Vec::new(),
             extension_tool_executors: Vec::new(),
             dynamic_tools: turn.dynamic_tools.as_slice(),
         },
@@ -217,21 +212,20 @@ async fn mcp_parallel_support_uses_handler_data() -> anyhow::Result<()> {
         step_context.as_ref(),
         ToolRouterParams {
             tool_suggest_candidates: None,
-            deferred_mcp_tools: None,
-            mcp_tools: Some(vec![
-                mcp_tool_info(
+            tool_runtimes: vec![
+                mcp_runtime(mcp_tool_info(
                     "echo",
                     /*supports_parallel_tool_calls*/ true,
                     "mcp__echo__",
                     "query_with_delay",
-                ),
-                mcp_tool_info(
+                )),
+                mcp_runtime(mcp_tool_info(
                     "hello_echo",
                     /*supports_parallel_tool_calls*/ false,
                     "mcp__hello_echo__",
                     "query_with_delay",
-                ),
-            ]),
+                )),
+            ],
             extension_tool_executors: Vec::new(),
             dynamic_tools: turn.dynamic_tools.as_slice(),
         },
@@ -268,8 +262,7 @@ async fn tools_without_handlers_do_not_support_parallel() -> anyhow::Result<()>
         step_context.as_ref(),
         ToolRouterParams {
             tool_suggest_candidates: None,
-            deferred_mcp_tools: None,
-            mcp_tools: None,
+            tool_runtimes: Vec::new(),
             extension_tool_executors: Vec::new(),
             dynamic_tools: turn.dynamic_tools.as_slice(),
         },
@@ -325,8 +318,7 @@ async fn specs_filter_deferred_dynamic_tools() -> anyhow::Result<()> {
         step_context.as_ref(),
         ToolRouterParams {
             tool_suggest_candidates: None,
-            deferred_mcp_tools: None,
-            mcp_tools: None,
+            tool_runtimes: Vec::new(),
             extension_tool_executors: Vec::new(),
             dynamic_tools: &dynamic_tools,
         },
@@ -368,6 +360,10 @@ fn mcp_tool_info(
     }
 }
 
+fn mcp_runtime(tool_info: codex_mcp::ToolInfo) -> Arc<dyn CoreToolRuntime> {
+    Arc::new(McpHandler::new(tool_info).expect("MCP tool spec should build"))
+}
+
 #[tokio::test]
 async fn extension_tool_executors_are_model_visible_and_dispatchable() -> anyhow::Result<()> {
     let (mut session, turn) = make_session_and_context().await;
@@ -393,8 +389,7 @@ async fn extension_tool_executors_are_model_visible_and_dispatchable() -> anyhow
         step_context.as_ref(),
         ToolRouterParams {
             tool_suggest_candidates: None,
-            deferred_mcp_tools: None,
-            mcp_tools: None,
+            tool_runtimes: Vec::new(),
             extension_tool_executors: extension_tool_executors(&session),
             dynamic_tools: turn.dynamic_tools.as_slice(),
         },