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

# Error codes

> Refer to the error codes below for troubleshooting common issues with Nscale's serverless inference service.

| Status Code | Description                                                                       | Response Format |
| ----------- | --------------------------------------------------------------------------------- | --------------- |
| 401         | Invalid service token or unauthorized                                             | Error object    |
| 403         | Forbidden — insufficient permissions for the requested endpoint and operation     | Error object    |
| 404         | Model not found or unavailable                                                    | Error object    |
| 409         | Conflict — the resource was modified by another request (retry with a fresh copy) | Error object    |
| 429         | Insufficient credit                                                               | Error object    |
| 500         | Internal server error                                                             | Error object    |
| 503         | Service temporarily unavailable                                                   | Error object    |

### Common solutions

* **401 (Unauthorized)**: Verify your service token is valid and properly included in the Authorization header
* **403 (Forbidden)**: The error message includes the endpoint and operation that was denied and which scope tier (global, organization, or project) rejected the request. Check that your role has the required permissions for this endpoint.
* **404 (Not Found)**: Check that you're using a valid model ID
* **409 (Conflict)**: Another request modified the resource between your read and your update. Fetch the latest version of the resource and retry your request.
* **429 (Rate Limit)**: Review your available credit
* **500 (Server Error)**: If persistent, contact support with details about your request
* **503 (Service Unavailable)**: Retry your request after a short delay, using exponential backoff

### Error response format

```json theme={null}
{
  "error": {
    "message": "Error message describing what went wrong",
    "type": "<an error type>",
    "param": "<optional, additional details about the error>",
    "code": "<a specific error code>"
  }
}
```

<Card title="Contact Support" icon="headset" iconType="solid" href="mailto:helpdesk@nscale.com">
  If you encounter any of these errors and need further assistance, please Contact Support.
</Card>