X402 Check

{
  "accepts": [
    {
      "amountUsd": "$0.005",
      "assetLabel": "USDC (Base)",
      "network": "eip155:8453",
      "payTo": "0x5b32c973596078a967562ca652761404f19be0e9",
      "payToType": "eoa"
    }
  ],
  "challengeSource": "header",
  "checks": [
    {
      "id": "status_402",
      "level": "pass"
    },
    {
      "id": "challenge",
      "level": "pass"
    },
    {
      "id": "version",
      "level": "pass"
    },
    {
      "id": "payto_type",
      "level": "info"
    },
    {
      "id": "discovery",
      "level": "pass"
    }
  ],
  "discovery": {
    "hasInputSchema": true,
    "hasOutputExample": true,
    "method": "GET",
    "present": true
  },
  "elapsedMs": 201,
  "httpStatus": 402,
  "isX402": true,
  "method": "GET",
  "ok": true,
  "summary": {
    "fail": 0,
    "pass": 4,
    "warn": 0
  },
  "target": "https://horizonpulse.dev/api/pulse",
  "x402Version": 2
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://horizonpulse.dev/api/x402-check?method=GET&url=https%3A%2F%2Fhorizonpulse.dev%2Fapi%2Fpulse'

# 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 - 'https://horizonpulse.dev/api/x402-check?method=GET&url=https%3A%2F%2Fhorizonpulse.dev%2Fapi%2Fpulse' \
  | 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 $0.01 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.01" });
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 $0.01 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fhorizonpulse.dev%2Fapi%2Fx402-check
const res = await pay("https://horizonpulse.dev/api/x402-check?method=GET&url=https%3A%2F%2Fhorizonpulse.dev%2Fapi%2Fpulse");
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 $0.01 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.01"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://horizonpulse.dev/api/x402-check?method=GET&url=https%3A%2F%2Fhorizonpulse.dev%2Fapi%2Fpulse")
    print(res.status_code, res.text)