diff --git a/src/agents/agent-bundle-mcp-runtime.test.ts b/src/agents/agent-bundle-mcp-runtime.test.ts
index 4eab7cc91a6..0829016746e 100644
--- a/src/agents/agent-bundle-mcp-runtime.test.ts
+++ b/src/agents/agent-bundle-mcp-runtime.test.ts
@@ -1137,8 +1137,10 @@ process.on("SIGINT", shutdown);`,
         toolCount: 0,
         resources: { listChanged: true },
       });
-      await expect(fs.readFile(logPath, "utf8")).resolves.toContain(
+      await waitForFileText(
+        logPath,
         "reject tools/list method not found",
+        LIST_TOOLS_SERVER_LOG_TIMEOUT_MS,
       );
     } finally {
       await runtime.dispose();