Errors

Error responses are JSON with a consistent shape:

{
  "error": {
    "code": "QUOTA_EXCEEDED",
    "message": "Daily quota exceeded",
    "retryable": false
  }
}

code is a stable, machine-readable string — safe to branch on in client code. message is human-readable and may change wording over time. Some codes you'll see in practice today: RATE_LIMITED, MODEL_NOT_ALLOWED, CONVERSATION_NOT_FOUND, QUOTA_EXCEEDED, INVALID_REQUEST, FILE_REQUIRED, UNSUPPORTED_FILE_TYPE, FILE_SCAN_FAILED, FILE_NOT_FOUND, PLAN_NOT_FOUND, PLAN_NOT_PURCHASABLE.

A failed chat request never streams a raw provider or internal error message to the client — you'll get a generic message plus a reference id, with the real detail logged server-side.