diff --git a/scripts/gateway-watch-tmux.mjs b/scripts/gateway-watch-tmux.mjs
index 76a44a1ad53..b7f4b95dbe3 100644
--- a/scripts/gateway-watch-tmux.mjs
+++ b/scripts/gateway-watch-tmux.mjs
@@ -21,6 +21,7 @@ const TMUX_CHILD_ENV_KEYS = [
   RUN_NODE_CPU_PROF_DIR_ENV,
   "OPENCLAW_SKIP_CHANNELS",
   "OPENCLAW_STATE_DIR",
+  "OPENCLAW_TRACE_SYNC_IO",
 ];
 
 const sanitizeSessionPart = (value) => {
diff --git a/src/cli/gateway-cli/run.ts b/src/cli/gateway-cli/run.ts
index 5b23d01708d..3088ff8b520 100644
--- a/src/cli/gateway-cli/run.ts
+++ b/src/cli/gateway-cli/run.ts
@@ -159,7 +159,7 @@ function createGatewayCliStartupTrace() {
     async measure<T>(name: string, run: () => Awaitable<T>): Promise<T> {
       const before = performance.now();
       try {
-        return await withDiagnosticPhase(`cli.${name}`, run);
+        return await withDiagnosticPhase(name, run);
       } finally {
         const now = performance.now();
         emit(name, now - before, now - started);
diff --git a/src/infra/gateway-watch-tmux.test.ts b/src/infra/gateway-watch-tmux.test.ts
index f96304e32de..1e271eae8c1 100644
--- a/src/infra/gateway-watch-tmux.test.ts
+++ b/src/infra/gateway-watch-tmux.test.ts
@@ -43,6 +43,7 @@ describe("gateway-watch tmux wrapper", () => {
       env: {
         OPENCLAW_GATEWAY_PORT: "19001",
         OPENCLAW_PROFILE: "Dev Profile",
+        OPENCLAW_TRACE_SYNC_IO: "0",
         SHELL: "/bin/zsh",
       },
       nodePath: "/opt/node",
@@ -57,6 +58,7 @@ describe("gateway-watch tmux wrapper", () => {
     expect(command).toContain("'FORCE_COLOR=1'");
     expect(command).toContain("'OPENCLAW_GATEWAY_PORT=19001'");
     expect(command).toContain("'OPENCLAW_PROFILE=Dev Profile'");
+    expect(command).toContain("'OPENCLAW_TRACE_SYNC_IO=0'");
     expect(command).toContain("/opt/node");
     expect(command).toContain("scripts/watch-node.mjs");
     expect(command).toContain("gateway");