Pay with x402.
Get paid with x402.

Generate a wallet

A fresh keypair for Base (EVM) or Solana. Keep the private key in an env var — never send it anywhere, including here.

import { generatePrivateKey, privateKeyToAccount } from "viem/accounts";

const privateKey = generatePrivateKey();       // 0x... keep secret
const account = privateKeyToAccount(privateKey);
console.log("Base address:", account.address);

import { Keypair } from "@solana/web3.js";
import bs58 from "bs58";

const keypair = Keypair.generate();
console.log("Solana address:", keypair.publicKey.toBase58());
console.log("Secret key:", bs58.encode(keypair.secretKey));

Fund it

Send a few cents of USDC to the address from step 1, plus a trace of native gas (ETH on Base, SOL on Solana) — fees on both are fractions of a cent.

// Base — buy USDC on an exchange and withdraw to Base,
// or bridge from Ethereum at bridge.base.org
// Solana — buy/swap USDC on a Solana-compatible wallet
// or exchange, send to your generated address

// $0.01 + gas is enough for many payments through this site.

Pay & fetch the skill

Wrap fetch with a payment-aware client. It handles the 402 challenge, signs, retries, and returns the skill markdown. No account or API key needed on this side — just a funded wallet.

import { privateKeyToAccount } from "viem/accounts";
import { wrapFetchWithPaymentFromConfig } from "@x402/fetch";
import { ExactEvmScheme } from "@x402/evm";

const account = privateKeyToAccount(process.env.EVM_PRIVATE_KEY);

const fetchWithPayment = wrapFetchWithPaymentFromConfig(fetch, {
  schemes: [{ network: "eip155:8453", client: new ExactEvmScheme(account) }],
});

const res = await fetchWithPayment("https://YOUR-DEPLOY-URL/skill/base");
const skill = await res.text(); // the full x402 setup skill

Install & pick a facilitator

The facilitator verifies and settles payments on-chain for you. For real mainnet money, that means a free Coinbase Developer Platform account and a Secret API Key — the one piece of account setup in this whole guide, and it's on the receiving side, not the paying side.

import { createCdpFacilitatorClient } from "@coinbase/cdp-sdk/x402";

// pnpm add @x402/core @x402/express @x402/evm @coinbase/cdp-sdk
// Reads CDP_API_KEY_ID / CDP_API_KEY_SECRET from the environment
// (create a Secret API Key at portal.cdp.coinbase.com/api-keys/secret)
const facilitatorClient = createCdpFacilitatorClient();

Gate a route

Register the network, set a price and a payTo address, wrap the route. That's the whole paywall.

import express from "express";
import { paymentMiddleware, x402ResourceServer } from "@x402/express";
import { ExactEvmScheme } from "@x402/evm/exact/server";

const NETWORK = "eip155:8453"; // Base mainnet
const resourceServer = new x402ResourceServer(facilitatorClient)
  .register(NETWORK, new ExactEvmScheme());

const routes = {
  "GET /report": {
    accepts: {
      scheme: "exact",
      network: NETWORK,
      price: "$0.10",                 // what you charge
      payTo: "0xYourWalletAddress",   // where it lands
    },
  },
};

const app = express();
app.use(paymentMiddleware(routes, resourceServer, undefined, undefined, false));
app.get("/report", (req, res) => res.json({ report: "..." }));

Verify you're actually charging

Hit it unpaid. A real 402 with your price and address in the challenge means it's live.

$ curl -i https://your-server/report
HTTP/1.1 402 Payment Required
payment-required: eyJ4NDAyVmVyc2lvbiI6Mi...  # base64: your price + payTo