The foundational infrastructure for AI agents.

The only middleware that returns x402 and MPP challenges atomically — in the same 402 response. Your customers and their agents pay using whichever standard they support, without you writing two integrations or maintaining two flows.

HTTP/1.1 402 Payment Required
WWW-Authenticate: Payment id="EmkSnMIiqB5sJBD7vFbrWtgDgLr5FVRxQBSuI357WEY",
                  realm="api.example.com",
                  method="tempo",
                  intent="charge",
                  request="eyJhbW91bnQiOiIxMDAwMCIsImN1cnJlbmN5IjoiMHgyMG...",
                  expires="2026-04-28T12:25:24.610Z"
Content-Type: application/problem+json

{
  "type": "https://api.prudra.dev/problems/payment-required",
  "title": "Payment Required",
  "status": 402,
  "detail": "Payment required. See WWW-Authenticate (MPP) or X-PAYMENT-REQUIREMENTS (x402)."
}

Both x402 and MPP challenges arrive together. Calling agents pick whichever standard they support — and your endpoint never has to know the difference.

Built on Tempo as the primary settlement layer, with full EVM compatibility across Base, Ethereum, Optimism, Arbitrum, and Polygon. One integration, six chains. Add a chain by clicking a button — not by rewriting your stack.

No proprietary SDK conventions. No bespoke auth flow. No custom transport layer. Prudra speaks the standards your team already knows — OpenAPI 3.1 for the API surface, HMAC-SHA256 signed webhooks for events, Server-Sent Events for real-time streaming.

Prudra is designed for the time you don't have. Initialise once with your API key, mount two middleware functions on any route, ship the endpoint. The first paid agent request lands before you've finished your coffee.

import express from "express";
import { initialise } from "@prudra/core";
import { walletMiddleware, payMiddleware } from "@prudra/express";

initialise({
  apiKey: process.env.PRUDRA_API_KEY!,
});

const app = express();

app.use(walletMiddleware({ walletId: process.env.BYO_WALLET_ID }));

app.post(
  "/api/summarise",
  payMiddleware({ price: "0.01", description: "Text summarisation" }),
  (req, res) => res.json({ summary: "..." })
);

app.listen(3000);

The 402 challenge, payment verification, vault provisioning, and webhook delivery are handled by the middleware. Your route handler only runs after payment succeeds.