@x402/express?You wrote the service. You wired up the paymentMiddleware. Now put it where agents can find it โ on minia2a.uk, the marketplace that handles discovery, trials, and payments so you don't have to.
import { paymentMiddleware } from "@x402/express";
app.use(paymentMiddleware("0xYourAddress", {
"/my-api": {
price: "$0.05",
network: "base",
config: { description: "My x402 API" }
}
}));
One curl command. Takes 30 seconds. Your endpoint goes live in the minia2a directory immediately.
curl -X POST https://minia2a.uk/api/v1/services \
-H "Content-Type: application/json" \
-d '{
"url": "https://your-api.com/my-endpoint",
"name": "My API",
"description": "What your API does โ agents see this in search results",
"price": 0.05,
"categories": ["data", "crypto"]
}'
Check your listing is live and the x402 handshake works correctly.
curl -s -D - https://minia2a.uk/x402/find \
-H "Content-Type: application/json" \
-d '{"query":"your API name"}'
| โ Free to list | No listing fee. 5% fee only when you earn. |
| ๐ Agent discoverability | 318+ agent developers searching x402 endpoints. |
| ๐ 15 free trials | Every listed endpoint gets 15 free trial calls. Lower barrier for first-time callers. |
| ๐ฐ Auto payments | USDC on Base. x402 protocol handles the rest โ no invoicing, no accounts receivable. |
| ๐ Usage analytics | Per-endpoint trial and transaction stats on your dashboard. |
| ๐ Ecosystem visibility | Featured in x402 ecosystem, searchable by agents programmatically. |
When you use @x402/express, your API already speaks the x402 protocol. You've done the hard part. minia2a handles everything else agents need to find and use your API:
paymentMiddleware handles everything. No SDK to install, no API to integratex402-express (v1, deprecated) or @x402/express (v2), minia2a supports both. The x402 protocol handshake is backward-compatible โ if your endpoint returns 402 Payment Required with a valid WWW-Authenticate header, you're good.5% on paid transactions. Free trials: zero fee. Payment goes directly to your wallet โ minia2a never holds your funds.
Yes. Any price in USDC. The maxAmountRequired from your x402 header is what agents pay. minia2a displays it, doesn't change it.
minia2a monitors uptime. Prolonged downtime removes the listing until it recovers. No penalty โ just re-register when it's back.
x402 currently uses Base (Ethereum L2). If your payment address is on Base, you're compatible. Multi-chain support is in development.