Citation Check (Hallucinated and Retracted References)

Verify references before you publish or rely on them: up to 10 citations per call, as reference strings in any style, DOIs, or {title, authors, year, doi}. For each: status verified, mismatch (the work exists but authors, year or DOI are wrong, e.g. a real DOI that points to a different paper), uncertain or not_found (likely invented), the matched record with authors, year, venue, DOI and open-access link, the corrected issues, an APA-formatted reference, and a retraction flag with the notice date from Retraction Watch. Built for agents that write reports, papers or answers with sources. Sources: Crossref, OpenAlex, DataCite.

Run free trial ↗3 free calls per day with the example input. Paid: $0.005 USDC, no limit.

Call it

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

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agentsvc.io/api/v1/proxy/citation-check", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({"citations":["Kahneman D, Tversky A. Prospect theory: An analysis of decision under risk. Econometrica 1979.","Wakefield AJ et al. Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children. Lancet 1998.","doi:10.9999/fake.2020.12345"]}),
});
const { data, payment } = await res.json();  // payment.status "settling"; header X-Payment-Settle: sync returns payment.transaction

Input

Field	Type	Description
citations	any	1 to 10 references: strings, or {title, authors, year, doi}; or one string with one reference per line
doi	string	Single DOI (alternative to citations)
title	string	Single title (alternative to citations), optionally with authors and year
authors	array
year	integer

Output

Field	Type	Description
summary	object
citations	array
sources	string
checked_at	string