> ## Documentation Index
> Fetch the complete documentation index at: https://docs.unicyfalcon.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Error Handling

> Handle API errors and status codes

## Error Response Format

All errors return JSON:

```json theme={null}
{
  "success": false,
  "error": "error_code",
  "message": "Human-readable message",
  "details": { "field": ["Validation message"] }
}
```

## HTTP Status Codes

| Code | Meaning              | Typical cause                              |
| ---- | -------------------- | ------------------------------------------ |
| 200  | OK                   | Success                                    |
| 201  | Created              | Resource created                           |
| 400  | Bad Request          | Invalid parameters                         |
| 401  | Unauthorized         | Invalid or missing HMAC / API key          |
| 403  | Forbidden            | Plan insufficient or subscription inactive |
| 404  | Not Found            | Resource not found                         |
| 422  | Unprocessable Entity | Validation failed                          |
| 429  | Too Many Requests    | Rate limit exceeded                        |
| 500  | Server Error         | Internal error                             |

## Common Errors

* **401 Invalid Signature**: Check payload format `METHOD|URI|BODY|TIMESTAMP`, timestamp within 5 minutes, correct HMAC secret.
* **403 Plan insufficient**: Upgrade to API plan or higher at [Billing](https://app.unicyfalcon.com/billing).
* **429 Rate limit**: Wait for `Retry-After` seconds; consider upgrading plan.

Always check `success` and handle `error` / `message` in your client.