# 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 unknown (last checked 2026-10-22).

Searches across OpenAPI specifications to find matching operations or endpoints given a query input

## Facts

- Endpoint: POST https://pennyrail.vercel.app/api/p/nano/openapi.search--openapi-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-f9511310
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Wo0HVGe7nYsvcTSuyhFNz

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-f9511310 -d '<json body>'
```

Example prompt: Search the PennyRail OpenAPI registry to find any endpoint operations that match 'send an email notification' — I want to see which API paths and methods are available for that.

## When to prefer this

Choose this endpoint when an agent needs to dynamically discover which API operations are available for a given capability or task description at runtime, especially within the PennyRail ecosystem. Prefer it over static documentation lookups when you need machine-readable, structured OpenAPI operation details returned programmatically.

## Known failure modes

- Missing or malformed 'input' object returns a validation error
- No matching OpenAPI operations found returns empty results
- Overly broad queries may return too many low-relevance matches
- Payment failure (402) if USDC balance is insufficient before the call proceeds
- Timeout if the underlying OpenAPI index is temporarily unavailable

## How this service works

Machine-readable settlement service

## Output

Returns a JSON object containing matched OpenAPI operations, endpoint paths, methods, descriptions, and schema details relevant to the search input 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-f9511310/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)