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

# Environment Variables

> System-provided environment variables available in your MCP server deployments

Alpic automatically provides system environment variables to your MCP server deployments. These variables are set automatically and cannot be overridden by users.

## System environment variables

### ALPIC\_HOST

**Available at:** Both build and runtime

The hostname of your environment's MCP server URL. Used internally to treat the deployed host as an internal host (like `localhost`) when it's used as the OAuth server.

```
ALPIC_HOST=server-123456.alpic.live
```

### ALPIC\_CUSTOM\_DOMAINS

**Available at:** Both build and runtime

A comma-separated list of custom domains that are configured for your environment. Used internally to treat the deployed host as an internal host (like `localhost`) when it's used as the OAuth server.

```
ALPIC_CUSTOM_DOMAINS=yourdomain.com,anotherdomain.com
```