X402

x402 Payment Skill

Make HTTP payments using the x402 protocol with stablecoins.

Overview

x402 is an open standard for internet-native payments. When an API endpoint requires payment, it responds with HTTP 402 Payment Required, including payment details in the response. The client then makes a stablecoin payment and retries the request with proof of payment.

How to Use

1. Send an HTTP request to the target endpoint
2. If you receive a 402 Payment Required response, parse the payment requirements from the response body
3. The response includes: price, payment network, token address, and recipient
4. Create a stablecoin payment transaction on the specified network
5. Resend the original request with the payment proof in the X-PAYMENT header

Supported Networks

• Base: eip155:8453
• Ethereum: eip155:1
• Arbitrum: eip155:42161
• Solana: solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp

Supported Tokens

• USDC
• EURC

Integration

import { paymentMiddleware } from "@x402/express";

app.use(
  paymentMiddleware({
    "GET /api/data": {
      accepts: [
        {
          scheme: "exact",
          network: "eip155:84532",
          maxAmountRequired: "100000",
          resource: "https://api.example.com/data",
        },
      ],
      description: "Access to data API",
    },
  })
);

Resources

• GitHub Repository
• Documentation
• Ecosystem

Source: x402-foundation/x402 — distributed by TomeVault.