# Base Address Nonce

> Base Address Nonce is a paid API for AI agents from 402.com.tr, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-13).

Returns the next transaction nonce, ETH balance, and contract status for any Base network address

## Facts

- Endpoint: GET https://402.com.tr/api/x402/base-nonce
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/base-address-nonce-fb97bc93
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_-YSE_ow_cuO-Mo1JuEvVW

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-address-nonce-fb97bc93
```

Example prompt: What's the current nonce, ETH balance, and contract status for Base address 0x742d35Cc6634C0532925a3b844Bc454e4438f44e? I need to know before I build my next transaction.

## When to prefer this

Use this endpoint when you need to prepare a Base transaction and need the correct nonce, when auditing whether an address is fresh or has prior activity, or when you need to quickly distinguish between a smart contract and a wallet on Base. It bundles nonce, ETH balance, and contract detection in a single call, saving multiple RPC round-trips.

## Known failure modes

- Invalid or malformed address returns a 400 error
- Address not found on Base (zero-activity address) may return nonce of 0 with zero balance
- Network congestion or RPC errors may cause timeouts
- Non-Base addresses (e.g. Ethereum mainnet) may return incorrect or misleading results

## How this service works

🆕 The next nonce for any Base address, plus its ETH balance and whether it is a contract. The count means different things either side of that line — transactions sent for a wallet, contracts deployed for a contract — so both are reported under their own name instead of one ambiguous number. What you need before building a transaction, or to tell a fresh address from a used one.

## Output

Returns the next nonce for the given Base address (labeled separately as transaction count for wallets vs contracts deployed for contract addresses), the address's current ETH balance, and a boolean indicating whether the address is a smart contract or an externally owned account (EOA).

## 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"
    },
    "pathParams": {
     "type": "object"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "address"
     ],
     "properties": {
      "address": {
       "type": "string",
       "description": "Address"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/base-address-nonce-fb97bc93/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from 402.com.tr](https://www.zero.xyz/host/402.com.tr/llms.txt)