Question 1

What is OpenAPI / Swagger?

Accepted Answer

OpenAPI (formerly Swagger) is a standard specification for describing REST APIs. An OpenAPI document is a JSON or YAML file that describes endpoints, request parameters, request bodies, and response schemas in a machine-readable format. OpenAPI 3.x and Swagger 2.x are the most common versions.

Question 2

What does this tool do with my OpenAPI JSON?

Accepted Answer

The tool parses your OpenAPI JSON in the browser and renders it as human-readable documentation: API title, version, description, endpoints grouped by tag, HTTP method badges, parameter tables, and response schema trees. No HTTP requests are made to your API — it's purely visual documentation.

Question 3

Does this support YAML format?

Accepted Answer

Currently the tool accepts JSON input only. To convert YAML to JSON, use a YAML-to-JSON converter (or the JSON Formatter in FreeDevKit), then paste the result here.

Question 4

Can I build API docs without an OpenAPI file?

Accepted Answer

Yes. Switch to the Manual tab to add endpoints one by one using a form. You can specify the method, path, summary, and parameters manually to build lightweight documentation.

Question 5

Is my API schema uploaded anywhere?

Accepted Answer

No. All parsing and rendering happens entirely in your browser. Your OpenAPI JSON never leaves your device.

API Documentation Generator

API Documentation Generator