Hosted facilitator (Base Sepolia)

Copy-paste seller setup for x402 batch-settlement. Public demo at facilitator.batchrail.io. Public builder: Capt. Riker (@BatchRail).

Try a paid call (testnet)

Live example resource — no repo clone required:

• Health: /health
• Paid route: GET /weather

A normal browser gets HTTP 402 (expected). An x402 client pays with Base Sepolia test USDC (batch-settlement), retries, and receives a small JSON payload. Uses facilitator.batchrail.io.

Env vars (yours)

FACILITATOR_URL=https://facilitator.batchrail.io
EVM_ADDRESS=0xYourReceiveAddressOnBaseSepolia

You never need BatchRail private keys. EVM_ADDRESS is your pay-to wallet.

Endpoints

Path	Meaning
/health	Service up
/stats	Public usage counters
/supported	Schemes & networks
POST /verify	Verify payment
POST /settle	On-chain settle

1. Minimal Express — one protected route

import express from "express";
import { paymentMiddlewareFromHTTP, x402ResourceServer } from "@x402/express";
import { HTTPFacilitatorClient } from "@x402/core/server";
import { BatchSettlementEvmScheme } from "@x402/evm/batch-settlement/server";

const NETWORK = "eip155:84532"; // Base Sepolia testnet
const payTo = process.env.EVM_ADDRESS;

const facilitatorClient = new HTTPFacilitatorClient({
  url: process.env.FACILITATOR_URL ?? "https://facilitator.batchrail.io",
});

const batchScheme = new BatchSettlementEvmScheme(payTo);
const resourceServer = new x402ResourceServer(facilitatorClient)
  .register(NETWORK, batchScheme);

const app = express();

app.get(
  "/weather",
  paymentMiddlewareFromHTTP(
    {
      accept: [{
        scheme: "batch-settlement",
        network: NETWORK,
        payTo,
        maxAmountRequired: "10000",
        resource: "https://your-host.example/weather",
        description: "Test weather (Base Sepolia)",
        mimeType: "application/json",
      }],
    },
    resourceServer
  ),
  (_req, res) => res.json({ ok: true, note: "paid on testnet" })
);

app.listen(4021);

Full examples: github.com/BatchRail/core.

2. MCP / agent-tool sellers

Same facilitator. One paid tool endpoint on Base Sepolia:

FACILITATOR_URL=https://facilitator.batchrail.io
EVM_ADDRESS=0xYourAddress
NETWORK=eip155:84532   // testnet only

// On tool call:
// 1) 402 + batch-settlement requirements (network + payTo)
// 2) verify/settle via FACILITATOR_URL
// 3) run tool, return result

Use the same BatchSettlementEvmScheme + HTTPFacilitatorClient as Express; only the MCP/HTTP adapter differs.

Gas & wallets

• Facilitator — BatchRail pays Sepolia gas
• Your EVM_ADDRESS — receives settled test USDC
• Payer / agent — needs Base Sepolia USDC to open a channel

USDC (Base Sepolia): 0x036CbD53842c5426634e7929541eC2318f3dCF7e

Questions → @BatchRail (Capt. Riker).