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

# Anthale API Authentication with Bearer API Keys

> Authenticate Anthale runtime API requests with a bearer API key, keep the key server-side, and understand common authentication failures.

Anthale authenticates runtime API requests with a server-side API key sent in the `Authorization` header.

## Header format

Send your Anthale API key as a bearer token:

```text theme={null}
Authorization: Bearer an_xxxxxxxxx
```

## Server-side only

Anthale API keys are server-side credentials and can be created [in the dashboard](/docs/learn/api-keys/create-an-api-key). Keep them in your secret manager or deployment platform, and do not ship them in browser code, mobile apps, or any other public client.

## Example

```text theme={null}
curl https://api.anthale.com -H 'Authorization: Bearer <your-anthale-api-key>'
```

## Authentication failures

Anthale returns `401` when the API key is missing or invalid. Anthale returns `403` when the request is authenticated but not allowed to access the resource.

For error handling guidance, read [Errors](/docs/api-reference/errors).

## Next steps

Next, return to [API Reference](/docs/api-reference), read [Errors](/docs/api-reference/errors), or create a key in [Create an API Key](/docs/learn/api-keys/create-an-api-key).