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

# API reference

> How to authenticate, where the full REST catalog lives, and how this tab is organized.

Programmatic access to Gateways uses **HTTPS** against the API host (see **[Base URL](/api/index#base-url)** on the main API page). This documentation set includes **authentication**, **every REST topic** (projects, resources, workspaces, billing, and more), and **example** request shapes.

## Where to read first

1. **[Authentication & API access](/api/00-authentication-access)** — Session **JWT**, **API keys** (`sk_`), **`X-API-Key`**, **WebSocket `?token=`**, and credential restrictions.
2. **[API documentation](/api/index)** — Master index: base URL, response formats, pagination, and a **numbered list of all API guides** with links.

Use the **API reference** tab sidebar to open any topic (Authentication, Projects, Resources, DNS, Functions, and so on).

## Authentication at a glance

```http theme={null}
Authorization: Bearer <session_jwt>
```

or, for API keys created under **Account → API keys** (via **`/api/users/api-keys`**):

```http theme={null}
X-API-Key: sk_…
```

See **[Authentication & API access](/api/00-authentication-access)** for the full rules.

## REST catalog

The detailed API pages are maintained as MDX topic guides. Start with **[API documentation](/api/index)** for the base URL, request conventions, response shapes, and the full list of REST areas.