DEV Community: ihen404

Building an Autonomous Web Scraper API Gated by x402 Micro-Payments on Base

ihen404 — Tue, 08 Sep 2026 18:58:11 +0000

Autonomous AI agents need clean web data, but micro-subscriptions and API key signups create friction. To solve this, I built and deployed x402 Web Scraper API—a pay-per-request web scraping service gated by HTTP 402 Payment Required micro-payments on Base.

Instead of managing accounts or monthly subscriptions, an AI agent requests scraped markdown directly, receives a 402 payment challenge for $0.005 USDC, settles on-chain via Base mainnet, and receives the structured data in a single flow.

🛠️ How It Works
Agent Requests Scrape: Sends a POST request to /api/scrape with a target URL.

Server Challenges: The server returns HTTP 402 Payment Required with payment parameters (amount, recipient address, asset address, and chain).

Agent Settles: The agent executes an on-chain transfer on Base Mainnet.

Data Returned: Upon payment verification, the server returns LLM-ready content.

🧪 Quick Start & Client Integration
You can integrate this with your agent using the official client library:

Bash
npm install x402-scraper-client

Here is a simple Node.js agent implementation intercepting the x402 payment flow:
import fetch from "node-fetch";

async function runAgent() {
const targetUrl = "https://news.ycombinator.com";
console.log(🤖 Agent requesting web scrape for: ${targetUrl});

const res = await fetch("https://x402-scraper-api-production-67a4.up.railway.app/api/scrape", {
method: "POST",
headers: { "Content-Type": "application/json" },
body: JSON.stringify({ url: targetUrl })
});

if (res.status === 402) {
const paymentReq = await res.json();
console.log("💰 x402 Payment Gate Triggered!");
console.log(" Protocol:", paymentReq.protocol);
console.log(" Network:", paymentReq.network);
console.log(" Asset:", paymentReq.asset);
console.log(" Amount:", paymentReq.amount, "units ($" + paymentReq.price_usd + " USD)");
console.log(" Recipient Wallet:", paymentReq.recipient);
} else {
const data = await res.json();
console.log("✅ Scraped Data:", data);
}
}

runAgent();

🔗 Resources & Specs
OpenAPI Spec: https://x402-scraper-api-production-67a4.up.railway.app/openapi.json

AI Plugin Manifest: https://x402-scraper-api-production-67a4.up.railway.app/.well-known/ai-plugin.json

GitHub Repository: ihen404/x402-scraper-api

I'd love to hear feedback or see what agent tools you're building with x402! Feel free to leave a comment or drop a PR on GitHub.

Building Machine-Payable APIs: Introducing x402 Web Scraper on Base

ihen404 — Sat, 05 Sep 2026 20:01:20 +0000

AI agents need clean web data, but traditional subscriptions, credit cards, and API keys create major friction for autonomous programmatic workflows. Today, I am launching x402 Scraper API—a web extraction service built natively around the HTTP 402 Payment Required standard.

How It Works

Instead of managing accounts or API keys, client agents send a standard POST request with a target URL. The API responds with an HTTP 402 status code containing precise on-chain payment parameters:

Network: Base Mainnet
Asset: USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913)
Price: $0.005 USDC
Recipient Wallet: 0x391e20e3f938d9aa3b39c7f4aa1cb6cbd6a9df28

Once settled on-chain, the client resends the request with the transaction proof header (X-Payment) to receive structured JSON containing page titles, meta descriptions, headings, and clean body previews.

Quick Start & Verification

Test the endpoint via curl:


bash
curl -i -X POST [https://x402-scraper-api-production-67a4.up.railway.app/api/scrape](https://x402-scraper-api-production-67a4.up.railway.app/api/scrape) \
  -H "Content-Type: application/json" \
  -d '{"url":"[https://news.ycombinator.com](https://news.ycombinator.com)"}'

Built with Node.js, Express, and @x402/express on Base Mainnet.
Try it out on Railway or integrate it into your Model Context Protocol (MCP) agent workflows!

---

### 2. X (Twitter) Launch Post

Monetize Express.js APIs for AI Agents in 3 Lines of Code with x402

ihen404 — Sat, 29 Aug 2026 19:15:50 +0000

AI agents are increasingly making programmatic requests, but traditional billing (credit cards, OAuth, complex API keys) creates friction for automated microtransactions.

With x402-express, you can monetize any Express.js endpoint using HTTP 402 payment requirements on Base in 3 lines of code.

1. Installation

bash
npm install x402-express

2. Implementation

Add the middleware to any route you want to protect:
javascript
const express = require('express');
const { x402Middleware } = require('x402-express');

const app = express();

app.get('/api/agent-data', x402Middleware({ price: '0.01' }), (req, res) => {
res.json({ message: "Payment verified via x402!" });
});

app.listen(3000, () => console.log('Server running on port 3000'));

3. Verification & Registry

GitHub Repository: github.com/IkeHentrel/x402-express
MCP Registry: io.github.ihen404/x402-express

When an unauthenticated agent hits your endpoint, x402-express interceptively returns an HTTP 402 Payment Required payload containing payment parameters, verifying settlements autonomously.

🌐 Paid API Specification

Endpoint: POST https://your-deployed-app.up.railway.app/api/scrape

Protocol: x402 (HTTP 402 Payment Required)

Price: $0.02 USDC per request

Network: Base (chainId: 8453)

Asset Contract: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 (USDC)

Payout Address: YOUR_BASE_WALLET_ADDRESS

1. Unauthenticated Request (HTTP 402 Challenge)

Send a standard POST request without payment headers:


bash
curl -i -X POST [https://your-deployed-app.up.railway.app/api/scrape](https://your-deployed-app.up.railway.app/api/scrape) \
  -H "Content-Type: application/json" \
  -d '{"url": "[https://news.ycombinator.com](https://news.ycombinator.com)"}'
Expected Response Header:
HTTP/1.1 402 Payment Required
X-Payment-Required: eyJzY2hlbWUiOiJleGFjdCIsInBheVRvIjoiMHhZT1V...
Paid Request (Machine-to-Machine via x402 Client)
AI agents using @ihentrel/x402-express or x402-fetch automatically parse the challenge header, sign a $0.02 USDC payment payload on Base, and retry:
import { fetchWithX402 } from 'x402-client';

const response = await fetchWithX402('[https://your-deployed-app.up.railway.app/api/scrape](https://your-deployed-app.up.railway.app/api/scrape)', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({ url: '[https://news.ycombinator.com](https://news.ycombinator.com)' })
});

const data = await response.json();
console.log(data.markdown); // Returns clean Markdown ready for LLM context