From Zero to Paid API Call in 3 curl Commands

You've read about x402. You know agents can pay agents with USDC. But you haven't tried it yet because it sounds complicated — wallets, Base, gas fees, smart contracts.

It's not complicated. It's three HTTP requests. That's it.

I'm going to show you exactly what to type, what you'll see, and why each step works. By the end, you'll have an agent wallet with real credits and have made your first paid API call. Copy, paste, run.

What You Need

Just curl. That's it. No browser extensions, no MetaMask, no Base ETH for gas. The platform handles everything server-side.

Step 1: Register — One Command, Instant Wallet

curl -X POST https://minia2a.uk/api/v1/register-simple \
  -H "Content-Type: application/json" \
  -d '{"name":"my-first-agent"}'

What just happened? The server generated a Base wallet and linked it to your agent name. The 500 credits are pre-loaded — you can spend them immediately. No blockchain transaction needed on your side because credits are managed off-chain by the platform. When you want to go on-chain (earn real USDC from other agents calling your API), you connect your own wallet.

Step 2: Discover — Find an API Your Agent Actually Needs

curl https://minia2a.uk/api/services

Step 3: Pay and Call — Your First x402 Transaction

curl -X POST https://minia2a.uk/x402/recall \
  -H "Content-Type: application/json" \
  -H "X-Wallet: 0xf16F0882de08315B438E9f3a2Abfb2d2E5d94ECA" \
  -d '{"action":"store","key":"favorite-color","value":"blue"}'

curl -X POST https://minia2a.uk/x402/recall \
  -H "Content-Type: application/json" \
  -H "X-Wallet: 0xf16F0882de08315B438E9f3a2Abfb2d2E5d94ECA" \
  -d '{"action":"retrieve","key":"favorite-color"}'

What's Happening Under the Hood

Every paid call goes through a three-step x402 handshake:

1. Your agent requests a service. It sends an HTTP request to the endpoint with an X-Wallet header.
2. The gateway checks credits. If you have enough, the payment is deducted from your credit balance. If not, you get an HTTP 402 response with payment instructions (price, recipient address, chain).
3. The service executes. Payment confirmed, the upstream API is called, and the result is returned to your agent.

The credits are managed off-chain for speed (no waiting for block confirmations on every $0.01 call). When you're ready to earn — by publishing your own paid API — you connect an on-chain wallet and receive USDC on Base directly.

Beyond curl: Using This in Real Agents

The same three commands work from any HTTP client. Here's the equivalent in Python, JavaScript, and Go:

Python

import requests

# 1. Register
r = requests.post("https://minia2a.uk/api/v1/register-simple",
    json={"name": "python-agent"})
wallet = r.json()["wallet"]

# 2. Call any paid service
r = requests.post("https://minia2a.uk/x402/recall",
    headers={"X-Wallet": wallet},
    json={"action": "store", "key": "hello", "value": "world"})
print(r.json())  # {"ok": true, "cost": "0.01 USDC", ...}

JavaScript / Node.js

// 1. Register
const res = await fetch("https://minia2a.uk/api/v1/register-simple", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({ name: "js-agent" })
});
const { wallet } = await res.json();

// 2. Call any paid service
const data = await fetch("https://minia2a.uk/x402/gas", {
  headers: { "X-Wallet": wallet }
}).then(r => r.json());
console.log(data);  // { chain: "base", gasPrice: "0.001", ... }

Go

// 1. Register
body := strings.NewReader(`{"name":"go-agent"}`)
resp, _ := http.Post(
    "https://minia2a.uk/api/v1/register-simple",
    "application/json", body)
// parse wallet from response

// 2. Call any service with X-Wallet header
req, _ := http.NewRequest("GET",
    "https://minia2a.uk/x402/time", nil)
req.Header.Set("X-Wallet", wallet)
client.Do(req)

What You Can Build With This

Once your agent can pay for API calls, the design space opens up:

• Research agent that pays for web search, scraping, and summarization as it needs them — no monthly subscription to a single provider
• Trading agent that pays for real-time gas prices, token security audits, DEX prices, and Polymarket data — composable, per-call, no API key management
• Content agent that pays for language detection, translation, grammar checking, and SEO metadata — each from a specialized provider, not one monolithic LLM API
• DevOps agent that pays for npm audits, pip audits, SSL checks, DNS lookups, and HTTP header analysis — composing security tooling on the fly

FAQ

Do I need crypto to start? No. The 500 free credits are pre-funded. You only need a real wallet when you want to earn money by publishing your own API.

How do credits work? 1 credit = $0.005 USD. Most services cost 2 credits ($0.01) per call. You get 500 free credits at registration, which is ~$2.50 worth of API calls — roughly 250 calls to $0.01 endpoints.

What happens when credits run out? You get an HTTP 402 response. You can buy more credits through the platform or connect an on-chain wallet for direct USDC payments.

Can I publish my own API and earn? Yes. Register a service at /api/register with your endpoint URL and price. When other agents call it, you earn USDC. The platform takes a 5% fee.

Is this production-ready? 299 services, 359K+ requests, 318 agents, and counting. The protocol (x402) is governed by the Linux Foundation with 40 members including Visa, Mastercard, Stripe, and Cloudflare. The marketplace is live and processing real payments.

What chains are supported? Base (USDC) is the primary settlement chain. Multi-chain support is on the roadmap.