ToolVet
78trust / 100

Fair Random

by AIMarket in Other

x402 APIPassing, checked 1 h ago

Verifiable random bytes for a draw, raffle or tie-break: an ECVRF output over your seed plus a proof anyone can check offline. The same seed always gives the same output, so publish the seed first.

POST https://modelmarket.dev/x402/fair-random

Last 30 days

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Status and outage history · Atom feed

Uptime
100%
Response time
464 ms typical, 867 ms slowest 5%
Last check
1 h ago
Next check
any minute now

How to call it

POST https://modelmarket.dev/x402/fair-random

Each call costs $0.006 in USDC on Base, paid with the request over x402.

Run a free test callOne unpaid request, the way an agent sends it. You see the payment challenge it gets back. Nothing is charged.

Example request

From the listing.

POST https://modelmarket.dev/x402/fair-random
content-type: application/json

{
  "seed": "raffle-2026-10-02:alice,bob,carol"
}

Parameters

ParameterTypeRequiredDescription
num_bytesintegerNooutput length, 1-64 (default 32)
seedstringYesthe seed or message the draw is bound to (up to 4096 bytes)

Example response

The provider's example. We can't check it without paying.

{
  "capability_id": "sortes.draw@v1",
  "receipt": {},
  "result": {},
  "service": "fair-random",
  "status": "ok"
}

Call it from code

The curl command shows the payment challenge. The JavaScript and Python versions pay and call, and never pay more than $0.006.

curl: see the payment challenge
# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://modelmarket.dev/x402/fair-random' \
  -H 'content-type: application/json' \
  --data-raw '{"seed":"raffle-2026-10-02:alice,bob,carol"}'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - -X POST 'https://modelmarket.dev/x402/fair-random' \
  -H 'content-type: application/json' \
  --data-raw '{"seed":"raffle-2026-10-02:alice,bob,carol"}' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode
JavaScript: pay and call
// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

// Pays at most $0.006 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.006" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.006 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fmodelmarket.dev%2Fx402%2Ffair-random&method=POST
const res = await pay("https://modelmarket.dev/x402/fair-random", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "seed": "raffle-2026-10-02:alice,bob,carol"
  }),
});
console.log(res.status, await res.text());
Python: pay and call
# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.006 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.006"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://modelmarket.dev/x402/fair-random",
        json={
            "seed": "raffle-2026-10-02:alice,bob,carol",
        },
    )
    print(res.status_code, res.text)

Security scan

  • No findings. We scan names, descriptions and tool definitions for hidden instructions and other prompt-injection patterns.

Recent checks

WhenResultHTTPTimePrice
1 h agoPassed402363 ms$0.006
5 h agoPassed402388 ms$0.006
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2 days agoPassed402812 ms$0.006