# Robinhood Chain Account Nonce Lookup

> Robinhood Chain Account Nonce Lookup is a paid API for AI agents from x402-services-production.up.railway.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-15).

Fetches the latest and pending transaction nonce for a Robinhood Chain (rhchain) address, enabling correct transaction construction.

## Facts

- Endpoint: POST https://x402-services-production.up.railway.app/api/rhchain/nonce
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/robinhood-chain-account-nonce-lookup-a3089a2e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_koDxOLirPq7EA8YSYBs2-

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 robinhood-chain-account-nonce-lookup-a3089a2e -d '<json body>'
```

Example prompt: What's the current nonce — both latest confirmed and pending — for address 0xAbC123... on Robinhood Chain so I can build my next transaction?

## When to prefer this

Use this endpoint when building or signing transactions specifically on Robinhood Chain (rhchain) and you need an accurate, up-to-date nonce that accounts for both confirmed and pending transactions. Prefer this over generic EVM nonce lookups when targeting rhchain specifically, as it is purpose-built for that network.

## Known failure modes

- Invalid or malformed Ethereum address returns an error response
- Address not found on Robinhood Chain may return zero nonce or an error
- Network or RPC connectivity issues may cause timeouts
- Missing required 'address' field in request body returns a validation error

## How this service works

Robinhood Chain account nonce (latest + pending) for building transactions. Send { address }.

## Output

Returns the current latest (confirmed) nonce and pending nonce for the specified Robinhood Chain address, giving the caller the exact sequence number needed to construct a valid next transaction without collision.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object"
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json"
     ],
     "type": "string"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/robinhood-chain-account-nonce-lookup-a3089a2e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-services-production.up.railway.app](https://www.zero.xyz/host/x402-services-production.up.railway.app/llms.txt)