@forgemeshlabs/pay-per-crawl-vercel

Vercel Edge Middleware that charges AI crawlers per page with x402 and MPP. Works in front of anything Vercel serves: a static site, Astro, SvelteKit, Vite, Nuxt, Remix, Hugo, Docusaurus. (Next.js projects: use @forgemeshlabs/pay-per-crawl-next, same engine.) Only Web APIs, DNS-over-HTTPS for search-engine verification. You keep 100%: no account, no custody.

npm install @forgemeshlabs/pay-per-crawl-vercel

middleware.js at the project root (next to package.json):

import { createPayPerCrawl } from "@forgemeshlabs/pay-per-crawl-vercel";
const ppc = createPayPerCrawl({ siteName: "My Site" }); // PAY_TO, PRICE_USD, MODE ... come from env; options win
export default ppc.middleware;
// Vercel needs `config` as a literal in this file; it cannot be re-exported.
export const config = { matcher: ["/((?!_vercel|favicon.ico).*)"] };

Then in the Vercel project settings → Environment Variables: PAY_TO = your wallet (0x address on Base), PRICE_USD = 0.01, MODE = monitor. Deploy. Watch the function logs for what bots would have paid, then set MODE=gate and redeploy to charge.

Environment (all optional if passed as options): PAY_TO, PRICE_USD (min 0.005), MODE (monitor default, gate to charge), FACILITATOR_URL, CLASS_POLICY, BOT_OVERRIDES, ALLOW_PATHS, TRUST_HEADER, MPP_SECRET, PRO_KEY.

The middleware also serves /.well-known/x402.json, /llms.txt and /agents.txt. Prefer Edge Functions for those? export default ppc.handlers.x402Json; in api/x402.js with a rewrite, or just let the middleware do it.

Notes

• A pure static project needs a package.json for the dependency; vercel.json with "outputDirectory": "public" (or your folder) keeps the HTML where it was. See examples/vercel-static.
• TRUST_HEADER defaults to x-forwarded-for and the right-most entry is used, which is the one Vercel appended. A client cannot forge a search-engine IP by prepending it.
• Replay lock and rDNS cache are per-isolate memory; pass store (any {get, put, delete}, e.g. Vercel KV / Upstash) for a shared one. On serverless this is best effort; the on-chain nonce is the hard guard.
• /_vercel/*, static assets and non-GET/HEAD requests pass free. Bugs and bad config fail open: the site never goes down because of the gate.
• Edge Middleware runs on every matched request, including bots that never pay. Vercel's Edge Middleware invocations are metered on paid plans; the free Hobby plan has a generous allowance.

How money flows

Crawler signs a USDC authorization; the middleware has the facilitator (PayAI by default) verify and settle, and serves the page only on a settlement transaction hash. USDC lands in PAY_TO.

MIT.