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

# Introduction

> API Reference for the VelumX Relayer

## Welcome

The VelumX Relayer API provides the infrastructure layer for gasless transaction sponsorship on Stacks. While we recommend using the **VelumX SDK**, you can interact with the Relayer directly via these REST endpoints.

<Card title="VelumX Relayer Endpoints" icon="bolt" href="/api-reference/endpoint">
  Explore the interactive API playground
</Card>

## Authentication

All API endpoints require a valid project API Key passed in the `x-api-key` header. You can generate and manage your keys in the [VelumX Dashboard](https://dashboard.velumx.xyz).

```bash theme={null}
curl -X GET "https://api.velumx.xyz/api/v1/config" \
     -H "x-api-key: YOUR_API_KEY"
```

> \[!WARNING]
> Never expose your `velumx_live_` keys in client-side code. Always use a backend proxy for production environments.