Openapi Spec Generator

# OpenAPI / Swagger Specification Generator
## When to Use

Use this skill when you need generate complete, production-ready OpenAPI 3.x and Swagger 2.0 specifications from natural language descriptions, code, or partial specs. Use this skill whenever the user mentions OpenAPI, Swagger, API spec, REST API documentation, YAML/JSON API schema, endpoint documentation, API...


Generate complete, valid OpenAPI 3.x or Swagger 2.0 specifications from descriptions, code, or partial specs.

## Workflow

### Step 1 — Gather Context

Before writing any YAML/JSON, ask (or infer from context) the following:

| Question | Why it matters |
|---|---|
| OpenAPI 3.x or Swagger 2.0? | Different `info`, `servers`/`host`, `components`/`definitions` structure |
| Output format: YAML or JSON? | YAML default unless user specifies JSON |
| What does this API do? | Sets `info.title`, `info.description`, tags |
| List of endpoints (or code to extract from)? | Core paths object |
| Authentication type(s)? | `securitySchemes` — see reference |
| Common data models or entities? | `components/schemas` / `definitions` |
| Any existing partial spec to extend? | Merge rather than overwrite |

If the user provides code (Express routes, FastAPI, Django URLs, Spring controllers, etc.), **extract endpoints automatically** — do not ask what the user already told you.