ToolVet
77trust / 100

Arc Allowance

by Token allowance check, Arc in Onchain & crypto

x402 APIPassing, checked 2 h ago

Allowance check on Arc, before an app asks for an approval: what owner has already approved to spender for a token (default USDC; add &token=0x... for another), in tokens and USD, whether it is unlimited, the owner's balance, whether the spender is a contract and its name if it is one our own code uses on Arc (Uniswap v4 PoolManager, UniversalRouter, Permit2, Circle Gateway Wallet, CCTP TokenMessenger, the launchpad router; never guessed), and risk signals (unlimited to an unknown contract, an…

GET
https://apexfaucet.xyz/api/x402/arc-allowance
Price
$0.001
per call in USDC
Uptime
100%
last 30 days
Response time
346 ms
945 ms slowest 5%
Last check
Passed
2 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

GET https://apexfaucet.xyz/api/x402/arc-allowance

Each call costs $0.001 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://apexfaucet.xyz/api/x402/arc-allowance?owner=0x024b82335C29Fa5606a8ea5c1D24FC9eAD50700C&spender=0x000000000022D473030F116dDEE9F6B43aC78BA3

Parameters

ParameterTypeRequiredDescription
ownerstringYesThe wallet that gave (or would give) the approval.
spenderstringYesThe contract or wallet allowed to spend.

Example response

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

{
  "data": {
    "allowance": null,
    "allowanceRaw": "115792089237316195423570985008687907853269984665640564039457584007913129639935",
    "isUnlimited": true,
    "ok": true,
    "owner": "0x024b82335c29fa5606a8ea5c1d24fc9ead50700c",
    "ownerBalance": 0.44577,
    "riskSignals": [
      "unlimited approval (to Permit2 (Uniswap))"
    ],
    "spender": "0x000000000022d473030f116ddee9f6b43ac78ba3",
    "spenderName": "Permit2 (Uniswap)",
    "symbol": "USDC",
    "token": "0x3600000000000000000000000000000000000000",
    "usdValue": null
  },
  "ok": true,
  "paid": 0.001
}

Call it from code

The curl command shows the payment challenge. The JavaScript and Python versions pay and call, and never pay more than $0.001.

curl: see the payment challenge
# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://apexfaucet.xyz/api/x402/arc-allowance?owner=0x024b82335C29Fa5606a8ea5c1D24FC9eAD50700C&spender=0x000000000022D473030F116dDEE9F6B43aC78BA3'

# 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://apexfaucet.xyz/api/x402/arc-allowance?owner=0x024b82335C29Fa5606a8ea5c1D24FC9eAD50700C&spender=0x000000000022D473030F116dDEE9F6B43aC78BA3' \
  | 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 $0.001 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%2Fapexfaucet.xyz%2Fapi%2Fx402%2Farc-allowance
const res = await pay("https://apexfaucet.xyz/api/x402/arc-allowance?owner=0x024b82335C29Fa5606a8ea5c1D24FC9eAD50700C&spender=0x000000000022D473030F116dDEE9F6B43aC78BA3");
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 $0.001 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.get("https://apexfaucet.xyz/api/x402/arc-allowance?owner=0x024b82335C29Fa5606a8ea5c1D24FC9eAD50700C&spender=0x000000000022D473030F116dDEE9F6B43aC78BA3")
    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
2 h agoPassed402273 ms$0.001
6 h agoPassed402385 ms$0.001
11 h agoPassed402346 ms$0.001
16 h agoPassed402359 ms$0.001
21 h agoPassed402370 ms$0.001
Show 10 older checks
25 h agoPassed402241 ms$0.001
30 h agoPassed402207 ms$0.001
34 h agoPassed402237 ms$0.001
38 h agoPassed402945 ms$0.001
42 h agoPassed402325 ms$0.001
46 h agoPassed402570 ms$0.001
2 days agoPassed402125 ms$0.001
2 days agoPassed402248 ms$0.001
2 days agoPassed402382 ms$0.001
3 days agoPassed402747 ms$0.001