I built pi-openapi-tools — a Pi extension that reads an OpenAPI/Swagger spec and dynamically registers one callable tool per API operation.

Instead of hand-writing wrappers for every endpoint, you point Pi at a spec URL and immediately start using generated tools.

• npm: pi-openapi-tools on npm
• Pi package: pi-openapi-tools on Pi
• GitHub: Repository

Why I built this

Most API-agent integrations still require too much manual glue code:

• mapping endpoints to functions
• defining parameter schemas
• maintaining naming consistency
• wiring auth/token handling
• repeating the process for every API

That slows experimentation and makes agent tooling fragile.

I wanted a runtime-first workflow:

spec → generated tools → live API calls

What the extension does

Given an OpenAPI or Swagger spec URL, pi-openapi-tools:

• Generates one Pi tool per operation
• Supports Swagger 2.0 and OpenAPI 3.x
• Builds structured parameter schemas automatically
• Resolves request bodies by media/content type
• Handles path, query, and header params
• Adds slash commands for managing generated toolsets

It also includes:

• prefix-scoped registrations (/swagger-tools:list-prefixes)
• prefix cleanup (/swagger-tools:remove-prefix)
• tool inspection (/swagger-tools:describe)
• token/auth helpers (/swagger-tools:auth)

60-second quickstart

Install:

pi install npm:pi-openapi-tools

Generate tools from Petstore:

/swagger-tools https://petstore.swagger.io/v2/swagger.json --prefix pet
/swagger-tools:list

You’ll immediately get generated tools such as:

• pet_getstoreorderbyid
• pet_postuser
• etc.

A few implementation details mattered a lot in practice:

• Prefix-scoped additive registration
  Multiple API toolsets can coexist cleanly.

• Stable naming + dedupe
  Generated names are sanitized and collision-safe.

• No unregister support in Pi? Stub instead.
  Removed tools become non-executable guidance stubs instead of silently disappearing.

• Content-type-aware serialization
  Request body handling follows declared spec media types (JSON, form-data, urlencoded, text, etc).

I also added a full walkthrough + simulation test:

• Tutorial: Petstore walkthrough
• Repo: GitHub repository

If you try it on large or messy specs, I’d especially love feedback on:

• operation naming ergonomics
• auth edge cases
• request body/media handling
• discoverability in very large APIs

If this is useful, feel free to star the repo and share your API use case.