Check whether AI agents can find your site.

Pay $0.10 for a signed HTTP audit of what an AI crawler actually sees on your page — GPTBot, ClaudeBot, PerplexityBot, OAI-SearchBot, not a browser render.

A passing check earns a dated badge and a registry listing. No account, no card, no human.

See the registry Read the blog For AI agents

Pay with x402 (USDC)
No account, no card
Real crawler, not a browser

GPTBot
ClaudeBot
PerplexityBot
OAI-SearchBot

GET / HTTP/1.1
Host: example.com
User-Agent: GPTBot/1.0
Accept: text/html

<html>
  <head></head>
  <body>
    <div id="app"></div>
    <script src="app.js"></script>
  </body>
</html>

Visible content
Soft 404 detected
www/bare domain duplicate
robots.txt accessible

How a check works

What we actually measured

We checked 104 live sites built by AI coding agents with a plain HTTP request — no browser, no JavaScript, exactly what an AI crawler does when it visits a page.

Read the full measurement: method, control group and fixes

61% empty shell without JavaScriptunder 300 characters of visible text
67% return 200 OK for a page that does not exist(soft 404)
40% serve www and the bare domain as duplicatesno redirect
12% have a dead www or a dead bare domain

None of it looks broken to a human in a browser. It is invisible to a crawler that never runs JavaScript — and the site has no way to know that happened.

How it works

1Pay per check.

$0.10 for one check over the x402 protocol — USDC on Base, no account, no card, no human on either side.
2We fetch your site as a bot.

The same request an AI crawler makes: no JavaScript, a self-identifying user agent, robots.txt, sitemap, the page itself, and a few soft-404 probes.
3You get a report with evidence.

Every finding quotes what we actually saw, not an opinion, plus a fix for your specific stack.
4A passing check earns a badge and a listing — free.

You pay for the analysis, not for the listing: a site that fails pays the same and is not listed, and nothing about a failure is ever published. Dated, machine-verifiable, free to look up at /api/check. Opt out with ?catalog=no.

Pricing

One check1 check$0.10$0.10/check

Add your site — free

Ask for a free check. If your site passes, it gets a listing in the catalog with a description and a real link. Being queued is not a promise of listing: only sites that pass are listed, and the queue is processed slowly.

Don't want to be listed? Disallow 402registry-check in your robots.txt or write to abuse@402registry.com. We honour both, and we never list a site that has opted out.

For AI agents

Everything below is a plain GET request. No API key beyond the x402 payment itself. The one exception is POST /submit, which is free and takes {"host":"example.com"}.

Manifest: https://402registry.com/.well-known/402registry.json
OpenAPI: https://402registry.com/openapi.json
Docs (JSON): https://402registry.com/docs
Buy a check: https://402registry.com/buy/{pack}?site={url}
Free lookup: https://402registry.com/api/check?url={url}
Badge: https://402registry.com/badge/{host}.svg