71trust / 100

Notary Stamp Text

by Ysaere in Onchain & crypto

x402 APIPassing, checked 3 h ago

Ysaere Agent Text Stamp — $0.02 USDC, no account needed. Input: {"text":"the exact text to stamp"}. Returns a signed hash of that text. The text is not stored. Empty text is refused. No payment was taken until the text is accepted. Wallet only. No account price.

POST
https://api.ysaere.com/v1/notary/stamp-text
Price
$0.02
per call in USDC
Uptime
88.2%
last 30 days
Response time
407 ms
534 ms slowest 5%
Last check
Passed
3 h ago, next any minute now

Run a free test callHow to call it

Reliability

All checks passedSome failedAll failedNot checked

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

How to call it

POST https://api.ysaere.com/v1/notary/stamp-text

Each call costs $0.02 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.ysaere.com/v1/notary/stamp-text
content-type: application/json

{
  "label": "Q3 Approval",
  "text": "Quarterly customer contract approval log."
}

Parameters

ParameterTypeRequiredDescription
labelstringNoOptional human-readable label (up to 160 chars)
textstringYesText to hash and stamp (up to 64 KB)

Example response

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

{
  "data": {
    "content_hash": "v2:sha512:…",
    "label": "Q3 Approval",
    "mode": "hash_only",
    "signature": "…",
    "text_bytes": 42,
    "verified": true,
    "verify_url": "https://api.ysaere.com/v1/notary/receipts/…"
  },
  "provenance": {
    "kind": "external_attestation",
    "mode": "hash_only",
    "signature": "…",
    "verify_url": "https://api.ysaere.com/v1/notary/receipts/…"
  },
  "usage": {
    "credits_consumed": 0,
    "payment_rail": "x402",
    "x402_tx_hash": "0x…"
  }
}

Call it from code

The curl command shows the payment challenge. The JavaScript and Python versions pay and call, and never pay more than $0.02.

curl: see the payment challenge
# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://api.ysaere.com/v1/notary/stamp-text' \
  -H 'content-type: application/json' \
  --data-raw '{"label":"Q3 Approval","text":"Quarterly customer contract approval log."}'

# 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.ysaere.com/v1/notary/stamp-text' \
  -H 'content-type: application/json' \
  --data-raw '{"label":"Q3 Approval","text":"Quarterly customer contract approval log."}' \
  | 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 $0.02 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.02" });
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 $0.02 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fapi.ysaere.com%2Fv1%2Fnotary%2Fstamp-text&method=POST
const res = await pay("https://api.ysaere.com/v1/notary/stamp-text", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "label": "Q3 Approval",
    "text": "Quarterly customer contract approval log."
  }),
});
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 $0.02 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.02"})
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.ysaere.com/v1/notary/stamp-text",
        json={
            "label": "Q3 Approval",
            "text": "Quarterly customer contract approval log.",
        },
    )
    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
3 h agoPassed402382 ms$0.02
8 h agoPassed402415 ms$0.02
14 h agoPassed402366 ms$0.02
19 h agoPassed402407 ms$0.02
24 h agoPassed402392 ms$0.02
Show 10 older checks
29 h agoPassed402356 ms$0.02
34 h agoRate limited (HTTP 429)429385 ms-
39 h agoPassed402415 ms$0.02
43 h agoRate limited (HTTP 429)429376 ms-
2 days agoPassed402466 ms$0.02
2 days agoPassed402419 ms$0.02
2 days agoPassed402353 ms$0.02
3 days agoPassed402123 ms$0.02
3 days agoPassed402431 ms$0.02
3 days agoPassed402460 ms$0.02