# PennyRail JSON Key Omitter

> PennyRail JSON Key Omitter 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).

Removes specified keys from a JSON object and returns the filtered result

## Facts

- Endpoint: POST https://pennyrail.vercel.app/api/f/json.omit?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-key-omitter-9b679412
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_bFJOdFR8VOb9gOfld7mgz

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-key-omitter-9b679412 -d '<json body>'
```

Example prompt: Strip the keys 'password' and 'token' from this JSON object before I send it to the client: {"user":"alice","password":"secret","token":"abc123","email":"alice@example.com"}.

## When to prefer this

Use this endpoint when you need a simple, paid, machine-readable service to strip named keys from a JSON object as part of an automated pipeline. Prefer it when you want a lightweight, stateless transformation with a predictable per-call cost of $0.001 USDC via x402 protocol, especially in agent workflows that already handle micropayments.

## Known failure modes

- Missing 'input' field in request body returns a validation error
- Malformed JSON input causes a parse error
- Specifying keys that don't exist in the object results in the object being returned unchanged
- Network or cold-start latency on Vercel serverless may add occasional delay
- Payment failure (insufficient USDC balance) returns a 402 response before processing

## How this service works

Machine-readable settlement service

## Output

Returns a JSON object containing the 'operation' field (indicating 'omit') and a 'result' field holding the original input object with the specified keys removed. Additional metadata fields may also be present.

## Request schema (JSON Schema)

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

## 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-key-omitter-9b679412/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)