# Agent Data Tools: ETH Balance Lookup by Wallet Address

> Agent Data Tools: ETH Balance Lookup by Wallet Address is a paid API for AI agents from agent-data-tools.revmesh2074.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-30).

Returns the native ETH (or chain-native token) balance of a given 0x wallet or contract address on a supported EVM chain

## Facts

- Endpoint: GET https://agent-data-tools.revmesh2074.workers.dev/op/balance?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent-data-tools-eth-balance-lookup-by-wallet-address-fd196b66
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_xjKb3uPUv9MqXgOQIszhw

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability agent-data-tools-eth-balance-lookup-by-wallet-address-fd196b66
```

Example prompt: What's the current ETH balance for wallet address 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045? Give me both the human-readable balance and the raw Wei amount, and tell me which chain and block it was read from.

## When to prefer this

Use this endpoint when you need a quick, cheap ($0.001 USDC) on-chain native token balance lookup for any EVM-compatible wallet or contract address without setting up your own RPC node or API key. It covers Base, Ethereum, Arbitrum, Optimism, and Polygon. Prefer this over full portfolio endpoints when you only need the native balance and not ERC-20 token holdings.

## Known failure modes

- Invalid or malformed 0x address returns an error response
- Address with no activity may return a balance of 0 rather than an error
- Network or RPC node issues may cause timeouts or temporary failures
- Unsupported chain IDs may not be resolved correctly
- Payment failure (x402) results in no charge and no data returned

## How this service works

Native ETH balance (eth_getBalance) of any 0x wallet address on Optimism at the latest block, in wei and in ETH. Use to check whether a wallet can pay gas or a transfer; for ERC-20 tokens use op_token_balance, for all holdings at once use wallet_portfolio. A malformed address is rejected with 400, uncharged.

## Output

Returns a JSON object with the wallet address, human-readable ETH balance (as a decimal string), raw balance in Wei, the chain name (e.g. Optimism), chain ID (e.g. 10), the native token symbol (e.g. ETH), and the block number at which the balance was read.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "address"
 ],
 "properties": {
  "address": {
   "type": "string",
   "description": "0x wallet or contract address"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "block": {
   "type": "number"
  },
  "chain": {
   "type": "string"
  },
  "symbol": {
   "type": "string"
  },
  "address": {
   "type": "string"
  },
  "balance": {
   "type": "string"
  },
  "chainId": {
   "type": "number"
  },
  "balanceWei": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent-data-tools-eth-balance-lookup-by-wallet-address-fd196b66/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agent-data-tools.revmesh2074.workers.dev](https://www.zero.xyz/host/agent-data-tools.revmesh2074.workers.dev/llms.txt)