redocly/redoc

Redoc is an open-source tool that turns an OpenAPI (also known as Swagger) definition file into a polished, interactive API reference website. An OpenAPI definition is a structured file (YAML or JSON) that describes what endpoints an API has, what data each endpoint accepts, and what it returns. Redoc reads that file and produces a clean, three-panel documentation page: a navigation menu on the left, the main documentation in the center, and request and response examples on the right. It solves the tedious problem of manually writing and maintaining API documentation. Instead of updating a separate website every time the API changes, developers maintain one source-of-truth definition file, and Redoc automatically generates the docs from it. You can use Redoc in several ways: run a single command in the terminal using npx to produce a static HTML file, drop a script tag into an existing web page, or embed it as a React component in a JavaScript application. It supports OpenAPI versions 3.1, 3.0, and Swagger 2.0. Organizations like Docker and Discourse use it for their public API documentation. Built in TypeScript, it is available as an npm package and can be served from a CDN with no build step required.