# PennyRail OpenAPI Search

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

Searches OpenAPI specifications for matching operations or endpoints using a natural-language or structured query input

## Facts

- Endpoint: POST https://pennyrail.vercel.app/api/p/nano/openapi.search--search-openapi?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: down
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pennyrail-openapi-search-79012e48
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_MtatQ6TXzrUV3F_E6FG8W

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-79012e48 -d '<json body>'
```

Example prompt: Search the PennyRail OpenAPI index for any endpoints related to payment settlement and return the matching operations with their schemas.

## When to prefer this

Choose this endpoint when you need to programmatically discover or search OpenAPI-defined operations within PennyRail's indexed catalog, especially in agent pipelines that need to dynamically find the right API endpoint before invoking it. Prefer this over manual spec browsing when automating API discovery workflows.

## Known failure modes

- Missing or malformed 'input' object returns validation error
- Empty or overly broad query returns too many or zero results
- Query terms not matching any indexed operation return empty result set
- Service unavailability on Vercel infrastructure returns 5xx error
- Payment failure via x402 protocol blocks access before search executes

## How this service works

Machine-readable settlement service

## Output

Returns a JSON object containing matching OpenAPI operation entries, including endpoint paths, HTTP methods, descriptions, and schema details relevant to the search query.

## 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-79012e48/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)