# PennyRail JSON Resource Node

> PennyRail JSON Resource Node is a paid API for AI agents from pennyrail.vercel.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-23).

Fetches and returns a JSON resource node value by path using a machine-readable settlement protocol over x402

## Facts

- Endpoint: POST https://pennyrail.vercel.app/api/f/json.get?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pennyrail-json-resource-node-e618568a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_QD8_pGWzJ2cnHWMtI5uNJ

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 pennyrail-json-resource-node-e618568a -d '<json body>'
```

Example prompt: Fetch the value at path 'user.balance' from the PennyRail JSON resource node — I need the raw result back.

## When to prefer this

Choose this endpoint when you need to retrieve a specific JSON value by path from PennyRail's resource node system and are operating in an x402 micropayment-enabled environment. It is well-suited for agents that need to access structured data fields programmatically with minimal cost ($0.001 USDC per call). Prefer alternatives if you need write access, bulk queries, or do not support x402 payment headers.

## Known failure modes

- Invalid or missing 'input' object returns a validation error
- Path not found in the resource node returns a null or empty result
- Payment failure over x402 (insufficient USDC balance, network error) blocks the request
- Malformed path string may cause unexpected resolution behavior
- Service unavailability on Vercel returns a 5xx error

## How this service works

Machine-readable settlement service

## Output

Returns a JSON object containing 'operation' (a string naming the operation performed) and 'result' (the resolved value at the requested path), along with any additional fields from the resource node.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "description": "{value,path}"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "operation",
  "result"
 ],
 "properties": {
  "result": {},
  "operation": {
   "type": "string"
  }
 },
 "additionalProperties": true
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/pennyrail-json-resource-node-e618568a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from pennyrail.vercel.app](https://www.zero.xyz/host/pennyrail.vercel.app/llms.txt)