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

# Response Codes

> HTTP status codes returned by the Verilock API.

The Verilock API uses standard HTTP status codes. **2xx** = success, **4xx** = client error, **5xx** = server error.

## Success Codes

| Code  | Name       | Description                                                   |
| ----- | ---------- | ------------------------------------------------------------- |
| `200` | OK         | Request succeeded. Response body contains the requested data. |
| `201` | Created    | Resource successfully created (sessions, API keys, webhooks). |
| `204` | No Content | Request succeeded with no response body (DELETE operations).  |

## Client Error Codes

| Code  | Name                 | Description                                                                       |
| ----- | -------------------- | --------------------------------------------------------------------------------- |
| `400` | Bad Request          | Malformed request body, missing fields, or invalid JSON.                          |
| `401` | Unauthorized         | API key is missing, invalid, or revoked.                                          |
| `403` | Forbidden            | Valid key but insufficient permissions. Check your plan or key scopes.            |
| `404` | Not Found            | Resource does not exist. Verify endpoint URL and resource ID.                     |
| `409` | Conflict             | State conflict (e.g., approving an already-declined session).                     |
| `422` | Unprocessable Entity | Well-formed request with semantic errors. See `details` for field-level messages. |
| `429` | Too Many Requests    | Rate limit exceeded. Respect the `Retry-After` header.                            |

## Server Error Codes

| Code  | Name                  | Description                                                                  |
| ----- | --------------------- | ---------------------------------------------------------------------------- |
| `500` | Internal Server Error | Unexpected error on our end. Include `X-Request-Id` when contacting support. |
| `503` | Service Unavailable   | Temporary unavailability. Retry with exponential backoff.                    |

## Error Response Format

All errors return a consistent JSON structure:

```json 422 Unprocessable Entity theme={null}
{
  "error": "validation_error",
  "message": "The given data was invalid.",
  "details": {
    "redirect_url": ["The redirect url must be a valid URL."],
    "document_type": ["The selected document type is invalid."]
  }
}
```

```json 429 Too Many Requests theme={null}
{
  "error": "rate_limit_exceeded",
  "message": "Too many requests. Please retry after 30 seconds.",
  "details": {
    "retry_after": 30
  }
}
```

<Tip>
  Every response includes an `X-Request-Id` header. Always include this when contacting support about a specific error.
</Tip>