x402 in the CDP SDK

npm install @coinbase/cdp-sdk

import {
  CdpX402Client,
  createX402Server,
  createCdpFacilitatorClient,
} from "@coinbase/cdp-sdk/x402";

npm install @coinbase/cdp-sdk @x402/core @x402/evm @x402/svm @x402/extensions

import { CdpX402Client } from "@coinbase/cdp-sdk/x402";
import { wrapFetchWithPayment } from "@x402/fetch";

// Reads CDP_API_KEY_ID, CDP_API_KEY_SECRET, CDP_WALLET_SECRET from env.
const client = new CdpX402Client();

const fetchWithPayment = wrapFetchWithPayment(fetch, client);
const response = await fetchWithPayment("https://api.example.com/paid-endpoint");

const USDC_BASE = "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913";

const client = new CdpX402Client({
  spendControls: {
    maxAmountPerPayment: { atomic: 10_000n, asset: USDC_BASE },
    maxCumulativeSpend: { atomic: 50_000n, asset: USDC_BASE },
    maxCumulativeSpendWindow: "24h",
    allowedNetworks: ["eip155:8453"],
  },
});

import express from "express";
import { createX402Server } from "@coinbase/cdp-sdk/x402";
import { paymentMiddlewareFromHTTPServer } from "@x402/express";

const app = express();

// Reads CDP_API_KEY_ID, CDP_API_KEY_SECRET, CDP_WALLET_SECRET from env.
const server = await createX402Server({
  routes: { "GET /report": { price: "$0.01", description: "AI-generated report" } },
});

// `server` IS an x402HTTPResourceServer — pass it to any x402 middleware.
app.use(paymentMiddlewareFromHTTPServer(server));
console.log("Receiving EVM payments at", server.payToEvmAddress);

import { x402ResourceServer } from "@x402/core/server";
import { ExactEvmScheme } from "@x402/evm/exact/server";
import { createCdpFacilitatorClient } from "@coinbase/cdp-sdk/x402";

// Reads CDP_API_KEY_ID and CDP_API_KEY_SECRET from env.
const facilitatorClient = createCdpFacilitatorClient();

// The vanilla x402 way to build a resource server — only the facilitator argument changes.
const server = new x402ResourceServer(facilitatorClient)
  .register("eip155:8453", new ExactEvmScheme());

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

const cdp = new CdpClient();
const account = await cdp.evm.getOrCreateAccount({ name: "agent" });

// paymentRequired is the x402 PaymentRequired object returned by a resource server
// (e.g. the body of a 402 response); acceptedIndex selects which entry in
// paymentRequired.accepts to sign.
const payment = await account.signX402Payment(paymentRequired, 0);

{ "eip155:137": "https://your-rpc-provider.example.com/polygon" }