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

# Authentication

> This section covers authenticating with Discount Drug Network (DDN) API endpoints.

## Authenticating with an API key

To authenticate, include an `Authorization` header in your request with the `x-ddn-client-key` token format, where `ddn_your-api-key-here` is the API key provided for your account.

```
Authorization: x-ddn-client-key ddn_your-api-key-here
```

Make sure to replace `ddn_your-api-key-here` with your actual API key.

## Creating and refreshing session

We use JWT auth to retrieve a token for the session. First, you must login using [/auth/login]('/api-reference/auth/login) and then refresh your session with [/auth/refresh]('/api-reference/auth/refresh).