Agent Intel Citation Verifier

{
  "checkedAt": "2026-10-23T09:35:17.408Z",
  "results": [
    {
      "apa": "LeCun, Bengio, Hinton (2015). Deep learning. Nature, 521, 436-444. https://doi.org/10.1038/nature14539",
      "authors": [
        "Yann LeCun",
        "Yoshua Bengio"
      ],
      "bibtex": "@article{lecun2015,\n  title = {Deep learning},\n  author = {Yann LeCun and Yoshua Bengio and Geoffrey Hinton},\n  journal = {Nature},\n  year = {2015},\n  volume = {521},\n  pages = {436-444},\n  doi = {10.1038/nature14539}\n}",
      "id": "10.1038/nature14539",
      "input": "10.1038/nature14539",
      "publisher": "Springer Science and Business Media LLC",
      "source": "https://api.crossref.org/works",
      "status": "verified",
      "title": "Deep learning",
      "type": "doi",
      "venue": "Nature",
      "year": 2015
    },
    {
      "apa": "Vaswani, Shazeer, Parmar, Uszkoreit, Jones, Gomez, Kaiser, Polosukhin (2017). Attention Is All You Need [Preprint]. arXiv. https://arxiv.org/abs/1706.03762",
      "authors": [
        "Ashish Vaswani",
        "Noam Shazeer"
      ],
      "bibtex": "@misc{vaswani2017,\n  title = {Attention Is All You Need},\n  author = {Ashish Vaswani and Noam Shazeer and Niki Parmar and Jakob Uszkoreit and Llion Jones and Aidan N. Gomez and Lukasz Kaiser and Illia Polosukhin},\n  year = {2017},\n  eprint = {1706.03762},\n  archivePrefix = {arXiv}\n}",
      "id": "1706.03762",
      "input": "arXiv:1706.03762",
      "source": "https://export.arxiv.org/api/query",
      "status": "verified",
      "title": "Attention Is All You Need",
      "type": "arxiv",
      "venue": "arXiv",
      "year": 2017
    }
  ],
  "source": "Crossref, arXiv, Open Library"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://api.fadeandco.workers.dev/api/agent-intel/citation-verifier' \
  -H 'content-type: application/json' \
  --data-raw '{"references":["10.1038/nature14539","arXiv:1706.03762","978-0-14-032872-1"]}'

# 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 - -X POST 'https://api.fadeandco.workers.dev/api/agent-intel/citation-verifier' \
  -H 'content-type: application/json' \
  --data-raw '{"references":["10.1038/nature14539","arXiv:1706.03762","978-0-14-032872-1"]}' \
  | 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 $0.001 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.001" });
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 $0.001 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fapi.fadeandco.workers.dev%2Fapi%2Fagent-intel%2Fcitation-verifier&method=POST
const res = await pay("https://api.fadeandco.workers.dev/api/agent-intel/citation-verifier", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "references": [
      "10.1038/nature14539",
      "arXiv:1706.03762",
      "978-0-14-032872-1"
    ]
  }),
});
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 $0.001 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.001"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://api.fadeandco.workers.dev/api/agent-intel/citation-verifier",
        json={
            "references": [
                "10.1038/nature14539",
                "arXiv:1706.03762",
                "978-0-14-032872-1",
            ],
        },
    )
    print(res.status_code, res.text)