# Blockchain Transaction Nonce Lookup

> Blockchain Transaction Nonce Lookup is a paid API for AI agents from biosfera.46-62-215-147.sslip.io, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-01).

Returns the confirmed (latest) and pending transaction nonce for a wallet address on Base, Ethereum, Arbitrum, Optimism, or Polygon.

## Facts

- Endpoint: GET https://biosfera.46-62-215-147.sslip.io/o/nonce?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/blockchain-transaction-nonce-lookup-6f6fa156
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_KJZZ-FegSWeFBaaplsU_c

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 blockchain-transaction-nonce-lookup-6f6fa156
```

Example prompt: What's the current confirmed and pending nonce for wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 on Ethereum mainnet so I can build my next transaction?

## When to prefer this

Use this endpoint when you need to construct, sequence, or debug EVM transactions across Base, Ethereum, Arbitrum, Optimism, or Polygon and need accurate nonce values. Prefer it over block explorers when you need both confirmed and pending nonce in a single programmatic call, or when diagnosing stuck/dropped transactions due to nonce gaps.

## Known failure modes

- Invalid address format (not a 0x-prefixed 40-hex-character string) returns an error
- Unsupported chain value returns an error — only base, ethereum, arbitrum, optimism, polygon are valid
- Network or RPC errors may result in a timeout or 5xx response
- Missing required query parameters (chain or address) returns a validation error
- Address with no transaction history returns nonce of 0 for both confirmed and pending

## How this service works

Use when you need the next transaction nonce of an address on Base, Ethereum, Arbitrum, Optimism or Polygon: confirmed count (latest) and pending count, to build or debug transactions.

## Output

Returns the confirmed nonce (number of transactions included in finalized blocks, i.e. 'latest' count) and the pending nonce (including transactions in the mempool) for the given address on the specified chain. These values help agents correctly sequence new transactions or diagnose nonce-related issues.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "chain",
      "address"
     ],
     "properties": {
      "chain": {
       "enum": [
        "base",
        "ethereum",
        "arbitrum",
        "optimism",
        "polygon"
       ],
       "type": "string"
      },
      "address": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{40}$"
      }
     },
     "additionalProperties": false
    }
   },
   "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/blockchain-transaction-nonce-lookup-6f6fa156/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from biosfera.46-62-215-147.sslip.io](https://www.zero.xyz/host/biosfera.46-62-215-147.sslip.io/llms.txt)