# shelf.thirdmade.net Transaction Nonce Lookup

> shelf.thirdmade.net Transaction Nonce Lookup is a paid API for AI agents from shelf.thirdmade.net, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Returns the current transaction nonce for any EVM address on Base or Ethereum, enabling agents to construct valid transactions.

## Facts

- Endpoint: GET https://shelf.thirdmade.net/probe/nonce
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/shelf-thirdmade-net-transaction-nonce-lookup-afe0de6a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_oEePVGPnNTM3PRhll_zER

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 shelf-thirdmade-net-transaction-nonce-lookup-afe0de6a
```

Example prompt: What's the current transaction nonce for 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 on Base so I can build my next transaction?

## When to prefer this

Use this endpoint when an AI agent or transaction bot needs to programmatically retrieve the correct nonce before constructing or signing an EVM transaction on Base or Ethereum. Prefer this over manual RPC calls when operating in an agentic context with x402 micropayment support already in place. It complements the sibling block-height endpoint for full transaction preparation context.

## Known failure modes

- Invalid or malformed EVM address returns an error response
- Unsupported chain value returns an error (only 'base' and 'ethereum' are accepted)
- Address not yet on-chain (zero transactions) returns nonce of 0, which is valid
- Network or RPC unavailability may cause timeouts or 5xx errors
- Payment not included or insufficient causes 402 Payment Required

## How this service works

Current transaction nonce for any address on Base or Ethereum. Agent tx bots need this before sending transactions.

## Output

Returns the current transaction nonce (integer) for the queried EVM address on the specified chain (Base or Ethereum). The nonce represents the number of confirmed transactions sent from that address, and is the value an agent must include when constructing the next outgoing transaction.

## 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": {
      "chain": {
       "type": "string",
       "description": "base (default) or ethereum"
      },
      "address": {
       "type": "string",
       "description": "EVM 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/shelf-thirdmade-net-transaction-nonce-lookup-afe0de6a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from shelf.thirdmade.net](https://www.zero.xyz/host/shelf.thirdmade.net/llms.txt)