ToolVet
80trust / 100

Evm Allowance

by SiteCheck in Onchain & crypto

x402 APIPassing, checked 1 h ago

ERC-20 allowance an owner has granted a spender for one token: raw and human amount, with the token's symbol and decimals. unlimited is true when the allowance is at least 2^255, the usual approve-everything value. Read-only.

GET
https://api.sitecheck-api.workers.dev/api/evm/allowance
Price
$0.002
per call in USDC
Uptime
100%
last 30 days
Response time
55 ms
924 ms slowest 5%
Last check
Passed
1 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

How to call it

GET https://api.sitecheck-api.workers.dev/api/evm/allowance

Each call costs $0.002 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.

GET https://api.sitecheck-api.workers.dev/api/evm/allowance?chain=base&owner=0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045&spender=0x2626664c2603336E57B271c5C0b26F421741e481&token=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Parameters

ParameterTypeRequiredDescription
chainstringNobase (default), ethereum, arbitrum, optimism or polygon
ownerstringYesToken owner, 0x…
spenderstringYesSpender, 0x…
tokenstringYesERC-20 contract, 0x…

Example response

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

{
  "amount": 1.157920892373162e+71,
  "chain": "base",
  "checkedAt": "2026-10-14T04:49:19.405Z",
  "disclaimer": "Information only, not financial advice.",
  "owner": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
  "raw": "115792089237316195423570985008687907853269984665640564039457584007913082113074",
  "source": "https://base-rpc.publicnode.com (eth_call allowance, decimals, symbol)",
  "spender": "0x2626664c2603336E57B271c5C0b26F421741e481",
  "token": {
    "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "decimals": 6,
    "symbol": "USDC"
  },
  "unlimited": true
}

Call it from code

The curl command shows the payment challenge. The JavaScript and Python versions pay and call, and never pay more than $0.002.

curl: see the payment challenge
# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://api.sitecheck-api.workers.dev/api/evm/allowance?chain=base&owner=0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045&spender=0x2626664c2603336E57B271c5C0b26F421741e481&token=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'

# 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 - 'https://api.sitecheck-api.workers.dev/api/evm/allowance?chain=base&owner=0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045&spender=0x2626664c2603336E57B271c5C0b26F421741e481&token=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913' \
  | 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 $0.002 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.002" });
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 $0.002 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fapi.sitecheck-api.workers.dev%2Fapi%2Fevm%2Fallowance
const res = await pay("https://api.sitecheck-api.workers.dev/api/evm/allowance?chain=base&owner=0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045&spender=0x2626664c2603336E57B271c5C0b26F421741e481&token=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913");
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 $0.002 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.002"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://api.sitecheck-api.workers.dev/api/evm/allowance?chain=base&owner=0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045&spender=0x2626664c2603336E57B271c5C0b26F421741e481&token=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913")
    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
1 h agoPassed40266 ms$0.002
6 h agoPassed40255 ms$0.002
10 h agoPassed40250 ms$0.002
14 h agoPassed40242 ms$0.002
18 h agoPassed402924 ms$0.002
Show 2 older checks
23 h agoPassed40265 ms$0.002
27 h agoPassed40244 ms$0.002