> For the complete documentation index, see [llms.txt](https://docs.railbridge.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.railbridge.ai/readme.md).

# Developer Platform

<h2 align="center">RailBridge AI Documentation</h2>

<p align="center">Merchant Operating System for AI Agent Payments</p>

{% columns %}
{% column width="50%" %}

### Get started in 5 minutes

Setting up your first API to receive stablecoin payments should be the easiest part of getting started. Compliant with Coinbase's x402 standard.

No guesswork, no complexity. Just your first successful agentic payment.&#x20;

<a href="/spaces/0qKSt55rjBTBXsOayqrg" class="button primary" data-icon="rocket-launch">Get started</a> <a href="/spaces/0qKSt55rjBTBXsOayqrg/pages/CMxQRprlZuNtAveIlGig" class="button secondary" data-icon="book">Documentation</a>
{% endcolumn %}

{% column width="50%" %}
{% code title="client.js" overflow="wrap" lineNumbers="true" expandable="true" %}

```javascript
import express from "express";
import { createRailbridgeFromEnv } from "@railbridgeai/merchant-sdk";

const app = express();
const port = 4025; 
const rb = createRailbridgeFromEnv(process.env);

app.get("/health", (_req, res) => {
  res.json({ status: "ok", service: "merchant-sdk-minimal" });
});

await rb.protectExpress(
  app,
  {
    apiId: "premium_api",
    method: "GET",
    path: "/api/premium",
  },
  async (_req, res) => {
    // Keep your business logic inside the handler.
    res.json({
      ok: true,
      source: "merchant-sdk-minimal",
      message: "premium content unlocked via RailBridge merchant SDK",
    });
  },
);

app.listen(port, () => {

});

```

{% endcode %}
{% endcolumn %}
{% endcolumns %}

<h2 align="center"></h2>

<p align="center">Follow our X for more updates.</p>

<table data-card-size="large" data-view="cards"><thead><tr><th></th><th></th><th></th><th></th><th data-hidden data-card-cover data-type="files"></th></tr></thead><tbody><tr><td><h4><i class="fa-x-twitter">:x-twitter:</i></h4></td><td>X</td><td>Join our Discord community to post questions, get help, and share resources with over 3,000 like-minded developers.</td><td><a href="https://x.com/RailBridgeAI" class="button secondary">Follow X</a></td><td></td></tr></tbody></table>


---

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