OpenAPI Spec Generator

Generate, validate, and maintain OpenAPI 3.x specifications for your REST APIs. Creates schemas from existing code, generates client SDKs, and produces interactive API documentation.

This skill helps you create comprehensive OpenAPI specifications either from scratch or by analyzing existing API routes. It validates specs against the OpenAPI standard, generates typed client SDKs in multiple languages, and produces Swagger UI or Redoc documentation.

When to use

Use when documenting existing APIs, designing new API contracts, generating client libraries for API consumers, or migrating from Swagger 2.0 to OpenAPI 3.x.

Examples

Generate spec from Express routes

Create an OpenAPI spec by analyzing existing route handlers

Analyze my Express API routes and generate a complete OpenAPI 3.1 specification with schemas

Generate TypeScript client SDK

Create a typed API client from an OpenAPI spec

Generate a TypeScript API client with proper error handling from this OpenAPI spec