Captcha generate · Captcha Generate

by Captcha generate

POSTBaseSolanaArbitrumPolygonMonadAvalancheeip155:1329OptimismFraxtaleip155:42220stellar:pubnetalgorand:wGHE2Pwdvd7S12BL5FaOP20EGYesN73ktiC1qzkkit8=

$0.001

per call · USD Coin on Base

Mint a stateless captcha challenge to gate your OWN endpoint: returns a human prompt plus a salted sha256 answer hash you keep and verify later (sha256(salt + normalized answer) === answerHash) - no server state, no shared secret. Types: math (arithmetic) or alnum (character code), difficulty 1–3. Deterministic tooling for running bot protection, not defeating it.

Endpoint

POST https://agent402.tools/api/captcha-generate

4

Calls / 30d

1

Unique payers / 30d

Aug 31

Last called

exact

Payment scheme

Call this service

TypeScript · @x402/fetch
import { wrapFetchWithPayment } from "@x402/fetch";
import { privateKeyToAccount } from "viem/accounts";

const account = privateKeyToAccount(process.env.PRIVATE_KEY);
const fetchWithPay = wrapFetchWithPayment(fetch, account);

const res = await fetchWithPay("https://agent402.tools/api/captcha-generate", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    "difficulty": 1,
    "type": "math"
  }),
});
const data = await res.json();
cURL
curl -X POST \
  "https://agent402.tools/api/captcha-generate" \
  -H "Content-Type: application/json" \
  -d '{"difficulty":1,"type":"math"}' \
  -H "X-PAYMENT: <signed x402 payment>"

Example response

{
  "algo": "sha256",
  "answerHash": "…",
  "prompt": "What is 3 + 4?",
  "salt": "…",
  "type": "math",
  "verify": "sha256(salt + answer.trim().toLowerCase().replace(/\\s+/g,'')) === answerHash"
}

Payment details

Pay to0xabf4fabd7c416fb67202e5f9002389fc75e2a9d0
AssetUSD Coin · 0x833589fcd6edb6e08f4c7c32d4f71b54bda02913
NetworksBase, Solana, Arbitrum, Polygon, Monad, Avalanche, eip155:1329, Optimism, Fraxtal, eip155:42220, stellar:pubnet, algorand:wGHE2Pwdvd7S12BL5FaOP20EGYesN73ktiC1qzkkit8=
Schemesexact, upto

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