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

# Errors

> How errors are represented in API responses

Permutive uses conventional HTTP response codes to indicate success or failure of an API request. In general, codes in the `2xx` range indicate success, codes in the `4xx` range indicate an error that resulted from the information provided in the request (e.g. a required parameter was missing), and codes in the `5xx` range indicate an error with Permutive's API.

## HTTP status codes

You may encounter the following response codes. Any unsuccessful response will contain more information to help you identify the cause of the problem.

| Response code                                               | Description                                                                                                              |
| ----------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------ |
| `200`   **OK**                                              | Everything worked as expected and the request succeeded.                                                                 |
| `400`   **Bad Request**                                     | The request could not be understood by the server, usually due to malformed syntax such as a missing required parameter. |
| `401`   **Unauthorized**                                    | The client has not provided a valid Authentication HTTP header.                                                          |
| `403`   **Forbidden**                                       | The client has provided a valid Authentication header, but it does not have permission to access this resource.          |
| `404`   **Not Found**                                       | The requested resource cannot be found or does not exist.                                                                |
| `500`, `502`, `503`, `504` <br /> **Internal Server Error** | The server encountered an error while processing your request and failed. Something went wrong on Permutive's end.       |

## Subcodes

If there has been an error (non-200 response), the body of the response will be a JSON object that describes the error in more detail.

To help you better understand what went wrong and reference the problem, the API defines an error subcode and human-readable messages for every type of error that can occur. The `docs` field provides a resource where you can find out more information about this error. If you wish to contact our support team about any API errors, you can reference the `request_id` of your request.

All error responses from the API follow a common format. Here's an example response to a request with an invalid API key:

```json theme={"dark"}
HTTP/1.1 401 Unauthorized
{
  "request_id": "e2cef6f6-296d-4044-b362-73fb2bce4a72",
  "error": {
    "status": "Unauthorized",
    "code": 2000,
    "message": "The API key provided is invalid.",
    "cause": "This key does not exist.",
    "docs": "https://developer.permutive.com/docs/errors/401/2000"
  }
}
```

Every field is guaranteed, other than `cause` which is optional.

<Tip>
  **Understanding errors**

  If you're unclear on what an error means, or want more help please get in touch using the chat widget or by emailing [Support](mailto:support@permutive.com).
</Tip>