402registry — does an AI agent actually see your site?

# 402registry > Checks whether AI agents and AI crawlers can actually see a website: a plain HTTP fetch with no JavaScript, the way GPTBot, ClaudeBot, PerplexityBot and OAI-SearchBot fetch pages. $0.01 per check over the x402 protocol (USDC on Base), no account, no API key. A passing check earns a dated badge and a free listing in a public catalog. Every finding quotes what the fetch actually returned, with a fix for the site's stack. The paid check is the product; the catalog listing is a free bonus that is earned by passing and never bought, and nothing about a failed check is published. ## Buy a check (x402) A GET without payment returns 402 with x402 v2 requirements in the PAYMENT-REQUIRED header. Sign them and repeat the request with the PAYMENT-SIGNATURE header. Lost the answer? Resend the identical request with the same payment header within 5 minutes of settlement (same wallet, same site): you get it again and nothing is charged. A 409 already_paid means that authorization was already settled; the body is the receipt. Never sign a new authorization for the same purchase. - [One check, $0.01](https://402registry.com/buy/one): 1 check, $0.01 per check. Add ?site=<https URL> to the paid request. One payment buys one check, run now; one site gets at most 3 checks per hour and 10 per day. ## Buy data - [Catalog snapshot, $0.005](https://402registry.com/buy/catalog): every site in the catalog as one JSON file, rendered at purchase — per site the findings by name and severity, the stack, the title and what the crawler saw without JavaScript. No parameters. The basic fields are free at https://402registry.com/registry.json. ## Free - [Look up a site](https://402registry.com/api/check): add ?url=<site>. Returns the last dated verdict, if the site was ever checked. - [Submit a site for a free check](https://402registry.com/submit): POST {"host":"example.com"}. Being queued is not a promise of listing. - [Catalog](https://402registry.com/registry): listed s

{ "openapi": "3.1.0", "info": { "title": "402registry", "version": "1", "description": "Pay-per-check discoverability audit: does an AI crawler actually see your site? Signed HTTP audit over the x402 protocol (USDC on Base) — no account, no card, no human.", "contact": { "name": "abuse", "email": "abuse@402registry.com" }, "x-guidance": "Buy a check: GET https://402registry.com/buy/one?site=<https URL of the site> answers 402 with x402 v2 payment require