Lookproof

Check reverse DNS for a domain's mail servers: up to five MX hosts, their IPv4 and IPv6 addresses, each PTR name and whether it resolves back to the same address (FCrDNS), with coded findings. Use when an agent must tell whether a domain's mail servers have matching reverse DNS, a common reason for rejected or spam-filed mail.

Open endpoint ↗

Price per call: $0.01
Chain: Base
Method: GET
Paid calls · 30 days: 1

Call it from code

This API is run by its own provider and paid directly through x402. We list it so you can find it; we don't route or hold the payment.

import { x402Client, wrapFetchWithPayment } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";

const client = new x402Client();
registerExactEvmScheme(client, { signer: agentAccount });

const pay = wrapFetchWithPayment(fetch, client);
const res = await pay("https://api.lookproof.dev/v1/mail/ptr", { method: "GET" });
console.log(await res.json());

https://api.lookproof.dev/v1/mail/ptr