Screen Name

{
  "hits": [
    {
      "list": "OFAC",
      "list_id": "<id>",
      "list_published": "<date>",
      "match": "exact",
      "matched_on": "<name>",
      "score": 1
    }
  ],
  "limitations": [
    "Screening signal only: not KYC, not a compliance determination, and not legal advice."
  ],
  "lists": [
    {
      "list": "UN",
      "published": "<date>",
      "sha256": "<64hex>"
    }
  ],
  "ok": true,
  "receipt": {
    "amount_usd": 0.02,
    "receipt_id": "g402-<16hex>",
    "tx_hash": "0x<64hex>"
  },
  "result": "match",
  "type": "sanctions-name-screen"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://twin.unykorn.org/screen/name' \
  -H 'content-type: application/json' \
  --data-raw '{"params":{"name":"Vladimir Putin","type":"individual"}}'

# 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://twin.unykorn.org/screen/name' \
  -H 'content-type: application/json' \
  --data-raw '{"params":{"name":"Vladimir Putin","type":"individual"}}' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

// 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 $0.02 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.02" });
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 $0.02 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Ftwin.unykorn.org%2Fscreen%2Fname&method=POST
const res = await pay("https://twin.unykorn.org/screen/name", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "params": {
      "name": "Vladimir Putin",
      "type": "individual"
    }
  }),
});
console.log(res.status, await res.text());

# 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 $0.02 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.02"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://twin.unykorn.org/screen/name",
        json={
            "params": {
                "name": "Vladimir Putin",
                "type": "individual",
            },
        },
    )
    print(res.status_code, res.text)