错误处理

{
  "error": {
    "message": "Insufficient credits",
    "type": "insufficient_quota",
    "code": "insufficient_credits",
    "param": null
  }
}

{
  "type": "error",
  "error": {
    "type": "authentication_error",
    "message": "Invalid API key"
  }
}

{
  "error": {
    "code": 400,
    "message": "model is required",
    "status": "INVALID_ARGUMENT"
  }
}