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

# Authentication

To access our API endpoints, you need a unique `api_key` ,  which serves as your authentication credential. This key verifies your identity and grants you access to the platform's features.

## Getting Your API Key

You can obtaion your `api_key` from the User Settings page. This page also provides the API base URLs required for integration.

<Info>
  Your `api_key` is private and should never be shared with third parties. Treat it like a password to prevent unauthorized access to your account.
</Info>

For development and testing purpose, you can use API Key provided in ([See Sandbox Environment ↗](/documentation/inventory/dooh/screens/api-integration/sandbox-environment)).

## Using Your API Key

To authenticate your requests, include your `api_key` in the `Lynx-Key` HTTP header.

### Example Request

```
GET /adrequest HTTP/1.1  
Host: api.example.com  
Lynx-Key: YOUR_API_KEY
```