Designed to keep
the HUMANS away
A reverse CAPTCHA system. Easy for AI agents. Hard for humans.
Verify that automated systems are accessing your service.
Integration in 60 Seconds
Add ClawCha to your site with just a few lines of code.
Get Your Keys
Register your domain to get API keys instantly. No email required.
curl -X POST https://clawcha.org/api/v1/register \
-H "Content-Type: application/json" \
-d '{"domain": "your-site.com"}'{
"site_key": "clw_site_abc123...",
"secret_key": "clw_secret_xyz789...",
"domain": "your-site.com"
}Add the Widget
Include the widget script and add a container element.
<script src="https://clawcha.org/api/v1/widget.js" async defer></script>
<div class="clawcha-widget"
data-sitekey="YOUR_SITE_KEY"
data-callback="onClawchaSuccess">
</div>Verify on Your Server
Verify the token server-side using your secret key.
const response = await fetch('https://clawcha.org/api/v1/verify', {
method: 'POST',
headers: {
'Content-Type': 'application/json',
'X-Secret-Key': process.env.CLAWCHA_SECRET_KEY
},
body: JSON.stringify({
challenge_id: challengeId,
response_token: token
})
});
const result = await response.json();
if (result.success) {
// Verified! This is an AI agent
}API Reference
Full integration instructions for robots: AGENTS.md
/api/v1/register
Register a new site and get API keys instantly.
/api/v1/challenge
Request a new challenge. Requires site key header.
/api/v1/submit
Submit a challenge answer. Returns a response token on success.
/api/v1/verify
Verify a response token server-side. Requires secret key.
Why ClawCha?
Instant for AI
Challenges are trivial for AI agents - hash computation, base64 decoding, real-time data streaming.
Hard for Humans
Try computing SHA256 in your head, or tracking 30 rapidly changing numbers. Humans can't.
Screenshot-Resistant
Streaming challenges change too fast to screenshot. Long strings are tedious to transcribe.
AI-Friendly Signup
No email required. Get your API keys instantly via a simple POST request.