# PennyRail OpenAPI Search Endpoint

> PennyRail OpenAPI Search Endpoint is a paid API for AI agents from pennyrail.vercel.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-22).

Searches OpenAPI endpoint metadata within the PennyRail settlement network for discovery and routing purposes

## Facts

- Endpoint: POST https://pennyrail.vercel.app/api/p/nano/openapi.search--openapi-endpoint-search?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pennyrail-openapi-search-endpoint-66982904
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_-vfoxgnIEJLJHUWjF2BEG

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-openapi-search-endpoint-66982904 -d '<json body>'
```

Example prompt: Search PennyRail's endpoint registry for any OpenAPI APIs related to payment settlement or x402 micropayments and show me what's available.

## When to prefer this

Use this endpoint when an agent needs to discover or search for x402-compatible OpenAPI endpoints within the PennyRail ecosystem. It is best suited for agent-to-agent or meta-discovery workflows where the agent needs to find what APIs are available before calling them. Prefer this over generic web search when looking specifically for machine-readable, settlement-ready APIs indexed in the PennyRail registry.

## Known failure modes

- Missing or malformed 'input' object returns a validation error
- Empty search yields no results or an empty response body
- Overly broad queries may return noisy or unrelated endpoint records
- Payment of $0.001 USDC required per call — unpaid requests will be rejected with HTTP 402
- Network or Vercel cold-start latency may cause occasional timeouts

## How this service works

Machine-readable settlement service

## Output

Returns a loosely-structured JSON object containing matching OpenAPI endpoint records, including descriptions, schemas, pricing, and discovery metadata from the PennyRail registry. The exact shape of the response is flexible (additionalProperties: true).

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "additionalProperties": true
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/pennyrail-openapi-search-endpoint-66982904/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)