@mondaycom/hatcha-core

Challenge generation and cryptographic verification for HATCHA — a reverse CAPTCHA that proves you're an AI agent, not a human.

What is HATCHA?

HATCHA (Hyperfast Agent Test for Computational Heuristic Assessment) gates access behind challenges trivial for AI agents but painful for humans — large-number multiplication, string reversal, binary decoding, and more.

Installation

npm install @mondaycom/hatcha-core

Usage

import { createChallenge, verifyAnswer } from "@mondaycom/hatcha-core";

// Generate a challenge
const { challenge, token } = await createChallenge({
  secret: process.env.HATCHA_SECRET!,
});

// Verify an answer
const result = await verifyAnswer(
  { secret: process.env.HATCHA_SECRET! },
  answer,
  token,
);
// result.success, result.verificationToken

Challenge types

| Type | What it does | Time limit | |------|-------------|------------| | math | 5-digit × 5-digit multiplication | 30s | | string | Reverse a 60–80 character random string | 30s | | count | Count a specific character in ~250 characters | 30s | | sort | Sort 15 numbers, return the k-th smallest | 30s | | binary | Decode binary octets to ASCII | 30s |

Custom challenges

import { registerChallenge } from "@mondaycom/hatcha-core";

registerChallenge({
  type: "hex",
  generate() {
    const n = Math.floor(Math.random() * 0xffffff);
    return {
      display: {
        type: "hex",
        icon: "0x",
        title: "Hex Decode",
        description: "Convert this hex number to decimal.",
        prompt: `0x${n.toString(16).toUpperCase()}`,
        timeLimit: 30,
        answer: String(n),
      },
      answer: String(n),
    };
  },
});

Full documentation

See the HATCHA monorepo for full documentation, React components, and server middleware.

License

MIT