Response Envelope

{
  "data": {},
  "meta": {
    "requestId": "req_123",
    "sessionId": "ses_123",
    "executionId": "exec_123",
    "lineageId": "lin_123",
    "timingMs": {
      "total": 132,
      "policy": 16,
      "route": 8,
      "tool": 91
    }
  },
  "error": null
}