List your endpoint on tools402.

What is sell-side

Sell-side is the publisher side of the tools402 marketplace. Community sellers list their own API endpoints — anything from a niche OCR model to a bespoke data enrichment service — and tools402 handles payment routing, replay protection, and agent discovery.

The marketplace has two tiers: first-party endpoints operated directly by tools402 (live catalog at /v1/_meta), and community endpoints listed by independent sellers. Community endpoints appear alongside first-party ones in /v1/_meta, which agents query to auto-discover tools.

Buyers are autonomous agents — not humans clicking a checkout button. They pay per HTTP request, in USDC on Base, without any human in the loop. That means your endpoint generates revenue even while you sleep.

How it works fees & flow

When a buyer agent calls your endpoint through tools402, the platform collects a USDC payment on-chain, verifies it, and issues a signed JWT that the buyer presents to your server. Your server verifies the JWT and serves the response. You withdraw your earnings to any Base wallet at any time.

There is no monthly minimum, no upfront listing fee, and no lock-in. If your endpoint gets zero calls, you pay nothing.

Quick start JWT verification

After a buyer pays, tools402 issues a signed JWT in the X-Payment-Verified header. Your endpoint verifies this JWT using the tools402 public key. Copy the snippet below — TypeScript uses our SDK (npm install @tools402/client, 2 lines); Python uses standard JWT libs (no tools402-specific install).

// npm install @tools402/client
import { verifyPaywallJWT } from "@tools402/client/paywall";

// In your Hono / Express / Bun.serve handler:
app.post("/v1/my-endpoint", async (c) => {
  const token = c.req.header("x-payment-verified");
  const ok    = await verifyPaywallJWT(token, {
    endpoint: "/v1/my-endpoint",
    minUSDC:  0.005,           // minimum acceptable price
  });
  if (!ok) return c.json({ error: "payment required" }, 402);

  // serve your response
  return c.json({ result: "…" });
});

# requires: pyjwt[crypto] + cryptography (standard JWT libs)
import jwt, requests

# Fetch the tools402 public key once (cache it at module scope)
PUBKEY_PEM = requests.get("https://tools402.dev/.well-known/audit-pubkey.pem").text

# In your FastAPI / Flask handler:
def my_endpoint(request):
    token = request.headers.get("x-payment-verified")
    if not token:
        return {"error": "payment required"}, 402
    try:
        payload = jwt.decode(token, PUBKEY_PEM, algorithms=["EdDSA"])
        assert payload["endpoint"] == "/v1/my-endpoint"
        assert payload["amount_usdc"] >= 0.005
    except Exception:
        return {"error": "payment required"}, 402
    return {"result": "…"}

Once your endpoint is ready, go to /publish to register it on the marketplace. You set the price, the description, and the category — tools402 handles discovery and settlement.

Pricing model

You set the price per call in USDC at listing time. There is no tiered pricing or subscription model — every call pays the same flat amount. You can update your price at any time from your seller dashboard.

For guidance on what to charge, see the /pricing page — it shows the full first-party catalog with prices across all 7 categories, which gives a useful baseline for community endpoints in the same category.

Get help

The fastest path is the /community page — it has the Discord link and the seller-focused channels. For technical issues with JWT verification or listing, open a thread in #sell-side. For billing questions, email hello@tools402.dev.