15trust / 100

Agent Intel Hallucination Claim Checker

by SiteCheck Agent Intel & Dev in Other

x402 APIFailing, checked 8 h ago

Checks the named entities in an AI answer (up to 5 capitalised names) against Wikidata: each name is marked found or not found, with its Wikidata ID and description, and sentences containing a year are listed for review. It checks that entities exist, not that claims about them are true, so a found entity can still have a wrong fact.

POST
https://api.fadeandco.workers.dev/api/agent-intel/hallucination-claim-checker
Price
$0.003
per call in USDC
Uptime
0.0%
last 30 days
Response time
-
no timed checks yet
Last check
Failed
8 h ago, next any minute now

Run a free test callHow to call it

Reliability

All checks passedSome failedAll failedNot checked

Latest check failed 8 h ago: Amount "0.003" is not in atomic token units

Status and outage history · Atom feed · Watch with other listings

How to call it

POST https://api.fadeandco.workers.dev/api/agent-intel/hallucination-claim-checker

Each call costs $0.003 in USDC on Base, paid with the request over x402.

Run a free test callOne unpaid request, the way an agent sends it. You see the payment challenge it gets back. Nothing is charged.

Example request

From the listing.

POST https://api.fadeandco.workers.dev/api/agent-intel/hallucination-claim-checker
content-type: application/json

{
  "text": "Marie Curie won the Nobel Prize in 1903. She later moved to Mars in 1921."
}

Parameters

ParameterTypeRequiredDescription
textstringYesThe model answer to check, 10 to 5000 characters

Example response

The provider's example. We can't check it without paying.

{
  "checkedAt": "2026-10-23T09:35:21.542Z",
  "entities": [
    {
      "description": "Polish-born French physicist and chemist (1867–1934)",
      "name": "Marie Curie",
      "status": "found",
      "wikidataId": "Q7186"
    },
    {
      "description": "set of annual international awards, primarily 5 established in 1895 by Alfred Nobel",
      "name": "Nobel Prize",
      "status": "found",
      "wikidataId": "Q7191"
    }
  ],
  "notFoundCount": 0,
  "note": "Existence check only: a found entity can still carry a wrong date or fact. Review the sentences with years yourself.",
  "sentencesWithYears": [
    "Marie Curie won the Nobel Prize in 1903.",
    "She later moved to Mars in 1921."
  ],
  "source": "https://www.wikidata.org/w/api.php"
}

Call it from code

The curl command shows the payment challenge. The JavaScript and Python versions pay and call, and never pay more than $0.003.

curl: see the payment challenge
# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://api.fadeandco.workers.dev/api/agent-intel/hallucination-claim-checker' \
  -H 'content-type: application/json' \
  --data-raw '{"text":"Marie Curie won the Nobel Prize in 1903. She later moved to Mars in 1921."}'

# 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/hallucination-claim-checker' \
  -H 'content-type: application/json' \
  --data-raw '{"text":"Marie Curie won the Nobel Prize in 1903. She later moved to Mars in 1921."}' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode
JavaScript: pay and call
// 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 $0.003 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.003" });
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 $0.003 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fapi.fadeandco.workers.dev%2Fapi%2Fagent-intel%2Fhallucination-claim-checker&method=POST
const res = await pay("https://api.fadeandco.workers.dev/api/agent-intel/hallucination-claim-checker", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "text": "Marie Curie won the Nobel Prize in 1903. She later moved to Mars in 1921."
  }),
});
console.log(res.status, await res.text());
Python: pay and call
# 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 $0.003 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.003"})
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/hallucination-claim-checker",
        json={
            "text": "Marie Curie won the Nobel Prize in 1903. She later moved to Mars in 1921.",
        },
    )
    print(res.status_code, res.text)

Security scan

No findings

We scan names, descriptions and tool definitions for hidden instructions and other prompt-injection patterns.

Recent checks

WhenResultHTTPTimePrice
8 h agoAmount "0.003" is not in atomic token units402742 ms$0.003
16 h agoAmount "0.003" is not in atomic token units402915 ms$0.003
24 h agoAmount "0.003" is not in atomic token units402740 ms$0.003
33 h agoAmount "0.003" is not in atomic token units40236 ms$0.003
41 h agoAmount "0.003" is not in atomic token units4021.1 s$0.003
Show 10 older checks
2 days agoAmount "0.003" is not in atomic token units40229 ms$0.003
2 days agoAmount "0.003" is not in atomic token units40246 ms$0.003
3 days agoAmount "0.003" is not in atomic token units402940 ms$0.003
3 days agoAmount "0.003" is not in atomic token units402808 ms$0.003
3 days agoAmount "0.003" is not in atomic token units40249 ms$0.003
4 days agoAmount "0.003" is not in atomic token units4021.2 s$0.003
4 days agoAmount "0.003" is not in atomic token units40245 ms$0.003
4 days agoAmount "0.003" is not in atomic token units40243 ms$0.003
4 days agoAmount "0.003" is not in atomic token units40245 ms$0.003
5 days agoAmount "0.003" is not in atomic token units40270 ms$0.003