Refresh invalidated Codex MCP clients without reloading configuration

apps/daemon/internal/agent/codex/mcp_cancellation.go

@@ -152,6 +152,5 @@ func (s *Session) cleanupCancelledMCP(ctx context.Context) error {
 	if json.Unmarshal(raw, &receipt) != nil || !slices.Equal(receipt.ServerNames, labels) {
 		return errors.New("codex: native MCP invalidation unconfirmed")
 	}
-	_, err = request("config/mcpServer/reload", nil)
-	return err
+	return nil
 }

apps/daemon/internal/agent/codex/mcp_cancellation_test.go

@@ -107,8 +107,8 @@ func TestMCPChildFirstObservedTerminalUsesNativeRootAttribution(t *testing.T) {
 	}
 }
 
-func TestExecutorCancelledMCPRequiresScopeCloseThenInvalidationAndReload(t *testing.T) {
-	for _, mode := range []string{"mcp-confirmed", "mcp-caller-cancelled", "mcp-stop-failed", "mcp-invalidate-unconfirmed", "mcp-reload-failed"} {
+func TestExecutorCancelledMCPRequiresScopeCloseThenInvalidation(t *testing.T) {
+	for _, mode := range []string{"mcp-confirmed", "mcp-caller-cancelled", "mcp-stop-failed", "mcp-invalidate-unconfirmed"} {
 		t.Run(mode, func(t *testing.T) {
 			e, root := executorFixture(t, mode)
 			e.base.cfg.view.MCP = cancellationMCPBindings("active", "late", "healthy")
@@ -227,11 +227,7 @@ func TestExecutorCancelledMCPRequiresScopeCloseThenInvalidationAndReload(t *test
 			if mode == "mcp-stop-failed" {
 				wantInvalidate = 0
 			}
-			wantReload := 0
-			if confirmed || mode == "mcp-reload-failed" {
-				wantReload = 1
-			}
-			if counts["mcpServer/invalidate"] != wantInvalidate || counts["config/mcpServer/reload"] != wantReload || counts["turn/interrupt"] != 1 || counts["thread/start"] != 1 || counts["initialize"] != 1 || counts["mcpServerStatus/list"] != 0 || len(pids) != 1 {
+			if counts["mcpServer/invalidate"] != wantInvalidate || counts["config/mcpServer/reload"] != 0 || counts["turn/interrupt"] != 1 || counts["thread/start"] != 1 || counts["initialize"] != 1 || counts["mcpServerStatus/list"] != 0 || len(pids) != 1 {
 				t.Fatal(counts, pids)
 			}
 		})

apps/daemon/internal/agent/codex/preparation_helpers_test.go

@@ -213,11 +213,6 @@ func TestPreparationFakeCodexProcess(t *testing.T) {
 			if executorMode == "mcp-invalidate-unconfirmed" {
 				result = McpServerInvalidateResponse{}
 			}
-		case "config/mcpServer/reload":
-			if executorMode == "mcp-reload-failed" {
-				_ = output.Encode(map[string]any{"id": frame.ID, "error": map[string]any{"code": -32603, "message": "reload rejected"}})
-				continue
-			}
 		case "environment/status":
 			if os.Getenv("OAC_TEST_PREPARATION_BLOCK") == "1" {
 				for {

packages/codex-runtime/README.md

@@ -14,6 +14,6 @@ Every captured thread's current configuration is checked before invalidation sta
 
 Success returns `{ "serverNames": ["<binding-label>"] }`, sorted and deduplicated, after selected client shutdown completes. Ready clients have entered the native `ClientState::Closed`; pending startup is cancelled. Existing prepared calls retain their original client and cannot redirect to a replacement. This receipt acknowledges local invalidation, not remote tool completion or replacement readiness.
 
-After the host `StopMCP` receipt and native invalidation receipt, the adapter calls maintained `config/mcpServer/reload`. Its dirty state applies through the existing native refresh flow before a subsequent Turn uses MCP. Reconciliation replaces closed clients and reuses unchanged healthy connections. No eager `mcpServerStatus/list` discovery, synthetic model Turn, polling delay or whole app-server restart establishes this fence.
+Invalidation marks each captured Session’s MCP runtime dirty while holding its existing refresh semaphore. Before a subsequent Turn uses MCP, the maintained native refresh flow reconciles its owned configuration, replaces closed clients and reuses unchanged healthy connections. The cancellation path does not reload configuration files or eagerly discover replacements; no synthetic model Turn, polling delay or whole app-server restart establishes this fence.
 
 The patch's `targeted_invalidation_*` Rust tests exercise closed-client replacement and unaffected connection identity through native reconciliation using controlled in-process transports. The Go adapter tests exercise cancellation latching, late starts, native call identity, host closure ordering, explicit declaration, receipt failures and Executor reuse. Native compilation and focused Rust tests must run in the qualified source build; source applicability alone does not qualify the binary.

packages/codex-runtime/invalidate-mcp.patch

@@ -366,7 +366,7 @@ diff --git a/codex-rs/core/src/session/mcp.rs b/codex-rs/core/src/session/mcp.rs
 index 46af2d3..9753960 100644
 --- a/codex-rs/core/src/session/mcp.rs
 +++ b/codex-rs/core/src/session/mcp.rs
-@@ -89,6 +89,29 @@ impl ElicitationReviewer for GuardianMcpElicitationReviewer {
+@@ -89,6 +89,30 @@ impl ElicitationReviewer for GuardianMcpElicitationReviewer {
  }
 
  impl Session {
@@ -388,6 +388,7 @@ index 46af2d3..9753960 100644
 +                .mcp_runtime
 +                .invalidate_servers(&names)
 +                .await;
++            session.mark_mcp_runtime_dirty();
 +            Ok::<_, anyhow::Error>(())
 +        })
 +        .await?