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

# API Gateway

> Merge local and remote endpoints under a single API surface

## Overview

The Gateway router creates a unified API surface that merges local and remote agent/team/workflow endpoints. It proxies requests to remote servers and includes health checking.

## Quick Start

```typescript theme={null}
import { createAgentRouter } from "@agentium/transport";
import { createGatewayRouter } from "@agentium/transport";
import express from "express";

const app = express();
app.use(express.json());

// Local agents are served normally
app.use("/api", createAgentRouter({ cors: true }));

// Gateway routes to remote endpoints
app.use("/api", createGatewayRouter({
  remotes: [
    {
      baseUrl: "https://us-east.api.example.com",
      agents: ["analyst", "researcher"],
      teams: ["research-team"],
    },
    {
      baseUrl: "https://eu-west.api.example.com",
      agents: ["translator"],
      workflows: ["translation-pipeline"],
      headers: { Authorization: "Bearer eu-token" },
    },
  ],
  healthCheckIntervalMs: 30_000,
}));

app.listen(3000);
```

## Health Monitoring

```bash theme={null}
GET /gateway/health
```

Returns:

```json theme={null}
{
  "remotes": {
    "https://us-east.api.example.com": true,
    "https://eu-west.api.example.com": false
  }
}
```

## Remote Endpoint Configuration

| Option       | Type                     | Description                                   |
| ------------ | ------------------------ | --------------------------------------------- |
| `baseUrl`    | `string`                 | Base URL of the remote server                 |
| `agents`     | `string[]`               | Agent names to proxy                          |
| `teams`      | `string[]`               | Team names to proxy                           |
| `workflows`  | `string[]`               | Workflow names to proxy                       |
| `headers`    | `Record<string, string>` | Auth headers for this remote                  |
| `healthPath` | `string`                 | Custom health check path (default: `/agents`) |

## SSE Streaming

The gateway transparently proxies SSE streams — `POST /agents/:name/stream` calls are forwarded with event stream passthrough.