# Swift Bot Labs EVM Balance Checker

> Swift Bot Labs EVM Balance Checker is a paid API for AI agents from x402-toolbox.swiftbotlab.workers.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-31).

Fetches native and ERC-20 token balances for a given EVM wallet address on a specified blockchain network

## Facts

- Endpoint: GET https://x402-toolbox.swiftbotlab.workers.dev/v1/evm/balance?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/swift-bot-labs-evm-balance-checker-91a11f51
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_MHbCmnpOBjx4LQKo-2976

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 swift-bot-labs-evm-balance-checker-91a11f51
```

Example prompt: What's the ETH and USDC balance of wallet 0x2481E29895b43e87e547a50fB0BB5aa1E70585EB on Base? Also check for the USDC token at 0x8335....

## When to prefer this

Choose this endpoint when you need a quick, no-registration balance lookup for an EVM-compatible address across major chains (Ethereum, Base, Arbitrum, Optimism, Polygon, BSC, Avalanche, Gnosis, and testnets) and want to pay per-call in USDC without managing API keys. It is ideal for lightweight agent workflows that need occasional on-chain balance checks without committing to a full blockchain data provider subscription.

## Known failure modes

- Invalid or malformed wallet address returns an error response
- Unsupported chain identifier causes a rejection
- Token contract address not found on the specified chain may return zero balance or an error
- Network timeouts from upstream RPC providers
- Payment failure via x402 if USDC funds are insufficient

## How this service works

62 small, deterministic utility APIs (DNS and e-mail checks, web extraction, EVM decoding, x402 checks, IP math, JSON/CSV, hashing, conversions). No account or API key: pay per call in USDC with x402.

## Output

Returns a JSON object with the queried wallet address, the chain name, the native token symbol and balance (e.g. ETH: 0.0012), and an array of ERC-20 token entries each containing the contract address, symbol, and balance. All balances are human-readable decimal strings.

## 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",
      "HEAD"
     ],
     "type": "string"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "queryParams": {
     "type": "object",
     "required": [
      "address"
     ],
     "properties": {
      "chain": {
       "type": "string",
       "description": "One of ethereum, base, arbitrum, optimism, polygon, bsc, avalanche, gnosis, base-sepolia, sepolia (or a chain id)"
      },
      "tokens": {
       "type": "string",
       "description": "Token contract addresses (optional)"
      },
      "address": {
       "type": "string"
      }
     },
     "additionalProperties": false
    },
    "discoverable": {
     "type": "boolean"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "tool": "evm-balance",
  "result": {
   "chain": "base",
   "native": {
    "symbol": "ETH",
    "balance": "0.0012"
   },
   "tokens": [
    {
     "token": "0x8335...",
     "symbol": "USDC",
     "balance": "1.25"
    }
   ],
   "address": "0x2481E29895b43e87e547a50fB0BB5aa1E70585EB"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/swift-bot-labs-evm-balance-checker-91a11f51/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-toolbox.swiftbotlab.workers.dev](https://www.zero.xyz/host/x402-toolbox.swiftbotlab.workers.dev/llms.txt)