# Base Wallet Balance, Token Holdings & Nonce Lookup

> Base Wallet Balance, Token Holdings & Nonce Lookup is a paid API for AI agents from ai-data-marketplace-1042299154756.us-central1.run.app, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-14).

Fetch native ETH balance, ERC-20 token balances, account type, and transaction nonce for any EVM wallet address on Base, Ethereum, or Arbitrum.

## Facts

- Endpoint: GET https://ai-data-marketplace-1042299154756.us-central1.run.app/api/v1/base_wallet_balance_token_holdings_nonce
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/base-wallet-balance-token-holdings-nonce-lookup-b561ab40
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Q6tASiLUa3DLA3s5B71aP

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 base-wallet-balance-token-holdings-nonce-lookup-b561ab40
```

Example prompt: What's the current ETH balance, USDC and WETH token holdings, and nonce for wallet address 0xAbC...123 on Base?

## When to prefer this

Choose this endpoint when you need a quick, multi-field on-chain snapshot of a wallet — combining native balance, ERC-20 holdings, account type, and nonce in a single call on Base, Ethereum, or Arbitrum. Prefer it over chain-specific block explorers when you want structured JSON output ready for agent consumption, or when you need to check multiple token balances simultaneously without multiple RPC calls.

## Known failure modes

- Invalid or malformed EVM address returns an error or empty result
- Unsupported chain value causes a lookup failure
- Specified ERC-20 contract address not found on the requested chain returns empty token balance
- Block tag out of range or not yet finalized may return an error
- Rate limiting or RPC provider downtime may cause transient failures

## How this service works

Audit one public site or compare up to five domains across llms.txt, OpenAPI, robots, sitemap, x402 metadata, and the discovery surfaces autonomous buyers rely on.

## Output

Returns a JSON object with: success flag, network name, account type (EOA or contract), transaction nonce, native asset balance (ETH) as a formatted string, and an array of token balances for any specified ERC-20 contracts (defaulting to USDC and WETH).

## 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": {
      "block": {
       "type": "string",
       "description": "Block tag or number; defaults to latest."
      },
      "chain": {
       "type": "string",
       "description": "base, ethereum, or arbitrum; defaults to base."
      },
      "tokens": {
       "type": "string",
       "description": "One to five comma-separated ERC-20 contract addresses. Defaults to official USDC and WETH."
      },
      "address": {
       "type": "string",
       "description": "EVM wallet or contract address."
      }
     },
     "additionalProperties": true
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "success",
      "network",
      "account_type",
      "nonce",
      "native_balance",
      "token_balances"
     ],
     "properties": {
      "nonce": {
       "type": "string"
      },
      "network": {
       "type": "string"
      },
      "success": {
       "type": "boolean"
      },
      "account_type": {
       "type": "string"
      },
      "native_balance": {
       "type": "object",
       "required": [
        "asset",
        "balance_formatted"
       ],
       "properties": {
        "asset": {
         "type": "string"
        },
        "balance_formatted": {
         "type": "string"
        }
       },
       "additionalProperties": true
      },
      "token_balances": {
       "type": "array",
       "items": {}
      }
     },
     "additionalProperties": true
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "nonce": "0",
  "network": "base",
  "success": true,
  "account_type": "eoa",
  "native_balance": {
   "asset": "ETH",
   "balance_formatted": "0.0"
  },
  "token_balances": []
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/base-wallet-balance-token-holdings-nonce-lookup-b561ab40/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ai-data-marketplace-1042299154756.us-central1.run.app](https://www.zero.xyz/host/ai-data-marketplace-1042299154756.us-central1.run.app/llms.txt)