ToolVet
81trust / 100

Notarize

by api.fairseal.io in Onchain & crypto

x402 APIPassing, checked 5 h ago

Anchor an AI agent decision or audit record to Base mainnet. Submit {schema, payload_hash (SHA-256 hex, 64 chars), metadata}; service queues into a Merkle batch and returns a receipt with pending_anchor status immediately. Full Merkle proof and on-chain anchor_tx available via free GET /v1/notarize/:receipt_id after batch anchors (within batch_threshold receipts or 120s). Include Idempotency-Key header to prevent double-charges on retry.

POST https://api.fairseal.io/v1/notarize

Last 30 days

All checks passedSome failedAll failedNot checked
Uptime
100%
Response time
71 ms typical, 71 ms slowest 5%
Last check
5 h ago
Next check
any minute now

How to call it

# See the payment challenge (nothing is charged)
curl -i -X POST "https://api.fairseal.io/v1/notarize" \
  -H "content-type: application/json" \
  -d '{"metadata":{"agent_id":"my-agent-v1","decided_at":"2026-09-12T10:00:00Z","decision_hash":"b94f6f125c79e3a5ffaa826f584c10d52ada669e6762051b826b55776d05a3d7","input_hash":"a665a45920422f9d417e4867efdc4fb8a04a1f3fff1fa07e998e86f7f7a27ae3"},"payload_hash":"e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855","schema":"agent_decision"}'
import { wrapFetchWithPayment } from "@x402/fetch";
import { x402Client } from "@x402/core/client";
import { ExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client().register(
  "eip155:8453",
  new ExactEvmScheme(privateKeyToAccount(process.env.AGENT_KEY)),
);
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? Preflight it first for $0.005:
// GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fapi.fairseal.io%2Fv1%2Fnotarize
const res = await pay("https://api.fairseal.io/v1/notarize", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({"metadata":{"agent_id":"my-agent-v1","decided_at":"2026-09-12T10:00:00Z","decision_hash":"b94f6f125c79e3a5ffaa826f584c10d52ada669e6762051b826b55776d05a3d7","input_hash":"a665a45920422f9d417e4867efdc4fb8a04a1f3fff1fa07e998e86f7f7a27ae3"},"payload_hash":"e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855","schema":"agent_decision"}),
});
console.log(await res.json());

Example input

{
  "metadata": {
    "agent_id": "my-agent-v1",
    "decided_at": "2026-09-12T10:00:00Z",
    "decision_hash": "b94f6f125c79e3a5ffaa826f584c10d52ada669e6762051b826b55776d05a3d7",
    "input_hash": "a665a45920422f9d417e4867efdc4fb8a04a1f3fff1fa07e998e86f7f7a27ae3"
  },
  "payload_hash": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
  "schema": "agent_decision"
}

Security scan

  • No findings. We scan names, descriptions and tool definitions for hidden instructions and other prompt-injection patterns.

Recent checks

WhenResultHTTPTimePrice
5 h agoPassed40271 ms$0.05