ToolVet
77trust / 100

Crypto Whales

by SiteCheck in Onchain & crypto

x402 APIPassing, checked 29 min ago

Large stablecoin and major-token transfers in the last few minutes on Ethereum, Base, Arbitrum, Optimism or Polygon: hash, block time, sender, receiver, amount and USD value at the Coinbase spot price, sorted by value. Labels only for a few known addresses; others are null. One token contract is read over public RPC, so the window is short. Information only, not financial advice.

GET
https://api.sitecheck-api.workers.dev/api/crypto/whales
Price
$0.003
per call in USDC
Uptime
100%
last 30 days
Response time
680 ms
808 ms slowest 5%
Last check
Passed
29 min 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://api.sitecheck-api.workers.dev/api/crypto/whales

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.

GET https://api.sitecheck-api.workers.dev/api/crypto/whales?blocks=20&chain=base&limit=3&minUsd=100000&token=USDC

Parameters

ParameterTypeRequiredDescription
blocksstringNoBlocks to scan back from the latest: ethereum 10 (default, max 25), base and optimism 20 (max 40), arbitrum and polygon 40 (max 80)
chainstringNoethereum (default), base, arbitrum, optimism or polygon
limitstringNoTransfers to return, 1 to 50, default 20
minUsdstringNoMinimum USD value per transfer, default 1000000, at least 10000
tokenstringNoUSDC (default), USDT, WETH, WBTC or cbBTC, where the chain has it

Example response

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

Example response, 74 lines
{
  "chain": "base",
  "checkedAt": "2026-10-15T06:45:34.462Z",
  "decimals": 6,
  "disclaimer": "Information only, not financial advice.",
  "minUsd": 100000,
  "note": "Transfers from one token contract only, in the block window shown, valued at the spot price now. Labels cover only the addresses listed in the bundled file; the rest are null.",
  "priceUsd": 1,
  "returned": 3,
  "scanned": 1559,
  "source": "base JSON-RPC (eth_blockNumber, eth_getLogs on the ERC-20 Transfer topic of USDC, eth_getBlockByNumber); Coinbase spot price USDC-USD",
  "token": "USDC",
  "tokenAddress": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
  "total": 39,
  "transfers": [
    {
      "amount": 476382.22,
      "block": 52628677,
      "from": {
        "address": "0x3fe04a59ebd38cf06080a6f60a98d124eb59392a",
        "kind": null,
        "label": null
      },
      "time": "2026-10-15T06:45:01.000Z",
      "to": {
        "address": "0x2192bc3b4028acc1113f2cd9ac2cba70c36520db",
        "kind": null,
        "label": null
      },
      "txHash": "0x9a31c1e50c5bdd94e1d79a2dc6e2a7817b84a9bbeff098c8da5bb15a48c828b2",
      "usd": 476382.22
    },
    {
      "amount": 473223.54,
      "block": 52628689,
      "from": {
        "address": "0x2192bc3b4028acc1113f2cd9ac2cba70c36520db",
        "kind": null,
        "label": null
      },
      "time": "2026-10-15T06:45:25.000Z",
      "to": {
        "address": "0x3fe04a59ebd38cf06080a6f60a98d124eb59392a",
        "kind": null,
        "label": null
      },
      "txHash": "0x47b226f0a3037b1d91255aebb5e1bb14ddde5485c1609e49afe3fc7dfa0ce815",
      "usd": 473223.54
    },
    {
      "amount": 338654.14,
      "block": 52628691,
      "from": {
        "address": "0x8d05e14ae19546f9f22d3c5b3470ef3337baa57c",
        "kind": null,
        "label": null
      },
      "time": "2026-10-15T06:45:29.000Z",
      "to": {
        "address": "0x3fe04a59ebd38cf06080a6f60a98d124eb59392a",
        "kind": null,
        "label": null
      },
      "txHash": "0xf9dbfec3c6c77f623f9b86363720fed89f1730a1bc79232bc45c534999bc6c0b",
      "usd": 338654.14
    }
  ],
  "truncated": true,
  "window": {
    "blocks": 20,
    "fromBlock": 52628674,
    "toBlock": 52628693
  }
}

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 'https://api.sitecheck-api.workers.dev/api/crypto/whales?blocks=20&chain=base&limit=3&minUsd=100000&token=USDC'

# 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/crypto/whales?blocks=20&chain=base&limit=3&minUsd=100000&token=USDC' \
  | 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.sitecheck-api.workers.dev%2Fapi%2Fcrypto%2Fwhales
const res = await pay("https://api.sitecheck-api.workers.dev/api/crypto/whales?blocks=20&chain=base&limit=3&minUsd=100000&token=USDC");
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.get("https://api.sitecheck-api.workers.dev/api/crypto/whales?blocks=20&chain=base&limit=3&minUsd=100000&token=USDC")
    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
29 min agoPassed402698 ms$0.003
5 h agoPassed402680 ms$0.003
9 h agoPassed402148 ms$0.003
19 h agoPassed402808 ms$0.003