Check

Last 30 days

Uptime

100%

Response time

305 ms typical, 349 ms slowest 5%

Last check

38 min ago

Next check

any minute now

How to call it

# See the payment challenge (nothing is charged)
curl -i -X POST "https://http-header-checker.underscoredone.com/check" \
  -H "content-type: application/json" \
  -d '{"follow_redirects":true,"method":"GET","url":"https://example.com"}'

import { wrapFetchWithPayment } from "@x402/fetch";
import { x402Client } from "@x402/core/client";
import { ExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client().register(
  "eip155:8453",
  new ExactEvmScheme(privateKeyToAccount(process.env.AGENT_KEY)),
);
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? Preflight it first for $0.005:
// GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fhttp-header-checker.underscoredone.com%2Fcheck
const res = await pay("https://http-header-checker.underscoredone.com/check", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({"follow_redirects":true,"method":"GET","url":"https://example.com"}),
});
console.log(await res.json());

Example input

{
  "follow_redirects": true,
  "method": "GET",
  "url": "https://example.com"
}

Example output

{
  "api_version": "1.0.0",
  "final_url": "https://example.com/",
  "headers": {
    "cache-control": "max-age=600",
    "content-length": "1256",
    "content-type": "text/html; charset=UTF-8",
    "server": "nginx"
  },
  "missing_security_headers": [
    "strict-transport-security",
    "content-security-policy"
  ],
  "redirect_chain": [
    {
      "status_code": 301,
      "url": "http://example.com"
    }
  ],
  "response_time_ms": 214,
  "status_code": 200,
  "url": "https://example.com"
}

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