agents.factstamp.dev

A two-cent probe of the FactStamp engine: one small claim in, one cited answer out, receipted. Send a dated figure, a company name, a DOI/arXiv id or a package@version and get the verdict, the value and the source it rests on with our retrieval time — the same engine and the same sources the full-price doors read. Unknown is a valid answer and nothing is invented. Paid per call in USDC on Base; no

Open endpoint ↗

Price per call: $0.02
Chain: Base
Method: POST
Paid calls · 30 days: 4

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://agents.factstamp.dev/probe", { method: "POST" });
console.log(await res.json());

https://agents.factstamp.dev/probe