Verify B20 token

Boolean verdict with reasons: is this address a real factory-issued B20 on Base? Checks the 0xB200 address prefix, ERC-20 readability, and whether the B20 feature set is activated on the registry. ?address=0x…

Input

Example output

{
  "address": "0x8335…2913",
  "isB20": false,
  "checks": {
    "prefixMatch": false,
    "erc20Readable": true,
    "registryActivated": false
  }
}

Try it — see the 402 challenge (free)

curl -i "https://agent402.tools/api/b20-verify?address=0x833589fcd6edb6e08f4c7c32d4f71b54bda02913"

The response is HTTP 402 Payment Required with exact payment requirements. Any x402 v2 client pays automatically and retries:

Paid call (JavaScript agent)

import { wrapFetchWithPayment } from "@x402/fetch";
import { x402Client } from "@x402/core/client";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agent402.tools/api/b20-verify?address=0x833589fcd6edb6e08f4c7c32d4f71b54bda02913");

Related tools