# Agent Data Desk – Token Balance Lookup

> Agent Data Desk – Token Balance Lookup is a paid API for AI agents from x402-seller.zshnfaizal.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-15).

Returns the on-chain token balance for a given wallet address on Base or Ethereum, paid per-call at $0.002 USDC via x402.

## Facts

- Endpoint: GET https://x402-seller.zshnfaizal.workers.dev/v1/token/balance
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent-data-desk-token-balance-lookup-50b6e0b0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_lozU5K5OHcBsb6Hg81a_i

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-desk-token-balance-lookup-50b6e0b0
```

Example prompt: What's the current USDC balance of wallet address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base mainnet?

## When to prefer this

Choose this endpoint when you need a quick, no-account, pay-per-call on-chain token balance lookup for Base or Ethereum without setting up API keys or a subscription. It supports native ETH, common ERC-20 aliases (USDC, USDT, DAI, WETH, cbBTC), and arbitrary contract addresses, making it versatile for DeFi agents, portfolio trackers, and eligibility checks. At $0.002 per call it is cost-effective for low-to-moderate frequency queries.

## Known failure modes

- Invalid or malformed wallet address returns an error response
- Unsupported token alias or invalid contract address yields an error
- Payment failure (insufficient USDC or x402 protocol error) results in a 402 response with no data
- Unsupported chain value (anything other than 'base' or 'ethereum') returns validation error
- RPC node unavailability may cause transient failures or timeouts

## How this service works

Pay-per-call data for AI agents: weather ($0.005), defi_yields ($0.002), token_balance ($0.002), markdown ($0.01). USDC on Base mainnet via x402 v2; no API keys, no accounts.

## Output

Returns a JSON object containing the queried wallet address, chain name, chain ID, token metadata (symbol, kind, contract address, decimals), balance as both a raw integer string and a human-readable formatted string, the RPC endpoint used, the block number at which the balance was fetched, and a UTC timestamp of when the data was retrieved.

## 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": [
      "address"
     ],
     "properties": {
      "chain": {
       "enum": [
        "base",
        "ethereum"
       ],
       "type": "string"
      },
      "token": {
       "type": "string",
       "description": "'eth' for native balance, an alias (usdc, usdt, dai, weth, cbbtc) or a 0x contract address."
      },
      "address": {
       "type": "string",
       "description": "0x-prefixed 20-byte address to query."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "chain",
      "address",
      "token",
      "balance"
     ],
     "properties": {
      "rpc": {
       "type": "string"
      },
      "chain": {
       "type": "string"
      },
      "token": {
       "type": "object",
       "properties": {
        "kind": {
         "type": "string"
        },
        "symbol": {
         "type": "string"
        },
        "address": {
         "type": [
          "string",
          "null"
         ]
        },
        "decimals": {
         "type": "integer"
        }
       }
      },
      "address": {
       "type": "string"
      },
      "balance": {
       "type": "object",
       "properties": {
        "raw": {
         "type": "string"
        },
        "formatted": {
         "type": "string"
        }
       }
      },
      "chain_id": {
       "type": "integer"
      },
      "fetched_at": {
       "type": "string"
      },
      "block_number": {
       "type": "integer"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "rpc": "mainnet.base.org",
  "chain": "base",
  "token": {
   "kind": "erc20",
   "symbol": "USDC",
   "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
   "decimals": 6
  },
  "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
  "balance": {
   "raw": "0",
   "formatted": "0"
  },
  "chain_id": 8453,
  "fetched_at": "2026-08-29T20:05:12.000Z",
  "block_number": 41234567
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent-data-desk-token-balance-lookup-50b6e0b0/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-seller.zshnfaizal.workers.dev](https://www.zero.xyz/host/x402-seller.zshnfaizal.workers.dev/llms.txt)