GET /base/balance $0.003/call
Query the ETH or ERC20 token balance of any wallet on Base mainnet with a single HTTP request. No RPC node, no API key, no account — your agent pays $0.003 in USDC per call via the x402 protocol.
Parameters
| name | required | description |
|---|---|---|
address | yes | wallet address (0x…) |
token | no | ERC20 contract; omit for native ETH |
Example
GET /base/balance?address=0x8491…&token=0x8335…
→ {"account":"0x8491…","symbol":"USDC","decimals":6,"balance":"12500000","formatted":"12.5","network":"base"}
Payment (x402)
Call without payment to receive HTTP 402 with a base64 envelope in the payment-required header — price, payTo, network (USDC on Base), and I/O schemas. Pay automatically with @x402/fetch:
const payFetch = wrapFetchWithPayment(fetch, client);
const res = await payFetch("https://402arcade.dev/base/balance?…");
No API keys. No accounts. Machine-readable: openapi.json · llms.txt · catalog