Wallet Balance on Base

Read the ETH and USDC balance of any address on Base mainnet (chain 8453) straight from the chain, plus transaction count and how many x402 calls the USDC covers. Use it to check your own agent wallet before a paid workflow, to verify a counterparty was paid, or to monitor treasury addresses. Params: address (required, 0x...).

Run free trial ↗3 free calls per day with the example input. Paid: $0.002 USDC, no limit.

Call it

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

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agentsvc.io/api/v1/proxy/evm-balance", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({"address":"0x622efA6Ceb83a5b6EdBC931332f4db68B7f74F27"}),
});
const { data, payment } = await res.json();  // payment.transaction = on-chain receipt

Input

Field	Type	Description
address *	string	EVM address on Base

Output

Field	Type	Description
address	string
network	base
chain_id	integer
eth	string	ETH balance as decimal string
eth_wei	string
usdc	string	USDC balance as decimal string (6 decimals)
usdc_atomic	string
usdc_contract	string
tx_count	integer
block_number	integer
x402_calls_affordable	object
checked_at	string

Example response (data)

{
  "address": "0x622efA6Ceb83a5b6EdBC931332f4db68B7f74F27",
  "network": "base",
  "chain_id": 8453,
  "eth": "0.0041",
  "eth_wei": "4100000000000000",
  "usdc": "12.5",
  "usdc_atomic": "12500000",
  "usdc_contract": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
  "tx_count": 17,
  "block_number": 41234567,
  "x402_calls_affordable": {
    "at_0_002": 6250,
    "at_0_005": 2500
  },
  "checked_at": "2026-09-09T12:00:00.000Z"
}