# x402 Base Tools – ETH & ERC-20 Balance Lookup

> x402 Base Tools – ETH & ERC-20 Balance Lookup is a paid API for AI agents from base.kagurazaka.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-29).

Returns ETH and ERC-20 token balances for a Base address, with USD values for ETH, stablecoins, and up to five held tokens priced from on-chain pools.

## Facts

- Endpoint: GET https://base.kagurazaka.dev/v1/balance?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-base-tools-eth-erc-20-balance-lookup-1d7944ad
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_UU8KR3fTIGA5iBDLHDaNl

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 x402-base-tools-eth-erc-20-balance-lookup-1d7944ad
```

Example prompt: What's the current ETH balance and total USD portfolio value for the Base wallet 0x5672...? Include USDC, WETH, and AERO balances if they have any.

## When to prefer this

Use this endpoint when you need both raw token balances and USD valuations for a Base address in a single call. It is ideal for portfolio summaries, pre-payment checks, and DeFi dashboards on Base. Prefer it over separate price and balance calls when you want aggregated USD totals including ETH and a broad default token list without specifying every address.

## Known failure modes

- Invalid or malformed wallet address returns an error
- Unknown token symbol or address not found in the default list returns no entry for that token
- Token without a liquid Uniswap v3 or Aerodrome pool may have no USD value
- More than 20 tokens specified returns a validation error
- Network congestion on Base may cause slow or timed-out RPC reads
- Address with zero balances returns empty token array and zero total_usd

## How this service works

The ETH balance and ERC-20 balances of an address on Base, for the tokens you name or a default list of well-known tokens (USDC, WETH, cbBTC, AERO, DAI, USDT, DEGEN, VIRTUAL and others), with USD values for ETH, stablecoins and up to five other held tokens priced from their pools.

## Output

A JSON object containing the address's ETH balance as a string, an array of token objects (each with symbol, amount, and USD value), the ETH USD value, and a total_usd figure summing all priced holdings.

## 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": {
      "tokens": {
       "type": "string",
       "description": "comma separated token addresses or symbols (up to 20); default well-known tokens"
      },
      "address": {
       "type": "string",
       "description": "the wallet or contract address"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "eth": {},
      "tokens": {},
      "address": {},
      "total_usd": {},
      "eth_usd_value": {}
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "eth": "0.0001",
  "tokens": [
   {
    "amount": "2.89",
    "symbol": "USDC",
    "usd_value": 2.89
   }
  ],
  "address": "0x5672...",
  "total_usd": 3.13,
  "eth_usd_value": 0.24
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-base-tools-eth-erc-20-balance-lookup-1d7944ad/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from base.kagurazaka.dev](https://www.zero.xyz/host/base.kagurazaka.dev/llms.txt)