# ERC-20 Token Balance Lookup

> ERC-20 Token Balance Lookup is a paid API for AI agents from store.agentexchange.work, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-15).

Returns the ERC-20 token balance for a given wallet address on a specified EVM chain, including human-readable and raw amounts.

## Facts

- Endpoint: GET https://store.agentexchange.work/chain/erc20-balance
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/erc-20-token-balance-lookup-c604e48e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_uP-0cFdG6k2UR_amcVope

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 erc-20-token-balance-lookup-c604e48e
```

Example prompt: What's the USDC balance (token contract 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48) for wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 on Ethereum?

## When to prefer this

Use this endpoint when you need a quick, pay-per-call on-chain ERC-20 balance read across multiple EVM chains (Base, Ethereum, Optimism, Arbitrum, Polygon, Gnosis) without managing API keys or subscriptions. Prefer this over node providers or indexers when you want minimal setup and micro-payment billing via x402/USDC.

## Known failure modes

- Invalid wallet address format returns an error
- Invalid or non-ERC-20 token contract address returns an error
- Unsupported chain name returns an error
- Payment failure (insufficient USDC or x402 misconfiguration) returns 402
- Token with zero balance still returns 0 rather than an error
- Network timeout or RPC unavailability may return 5xx

## How this service works

Any wallet's balance of any ERC-20 token (USDC, USDT, DAI, or any contract) via balanceOf, across Base, Ethereum, Optimism, Arbitrum, Polygon, Gnosis. The token-balance read wallet-tracking, copy-trade, treasury and trading agents poll constantly — the most-called RPC read after native balance. Live public RPC; undercuts onesource at $0.001.

## Output

A JSON object containing the chain name, token contract address, wallet address, human-readable balance (float), token decimals, and raw balance string (unscaled integer as returned by the contract).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "wallet",
      "token"
     ],
     "properties": {
      "chain": {
       "type": "string",
       "description": "base|ethereum|optimism|arbitrum|polygon|gnosis (default base)"
      },
      "token": {
       "type": "string",
       "description": "ERC-20 token contract address (0x...)"
      },
      "wallet": {
       "type": "string",
       "description": "Holder wallet address (0x...)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "balance": {
       "type": "number"
      },
      "decimals": {
       "type": "number"
      },
      "raw_balance": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/erc-20-token-balance-lookup-c604e48e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from store.agentexchange.work](https://www.zero.xyz/host/store.agentexchange.work/llms.txt)