## exceptions.AuthenticationError


The service rejected the credential, or the credential lacks a permission.


Usage

``` python
exceptions.AuthenticationError(
    message,
    /,
    *,
    backend=None,
)
```


Both are permanent until someone changes a setting. So an expired token that refreshes cleanly is not an error, and a refresh the token endpoint rejects is. A token endpoint that fails on the provider's side raises [ProviderError](exceptions.ProviderError.md#epistole.exceptions.ProviderError) instead.