OpenAPI DevTools von Andrew Walsh

OpenAPI DevTools features an algorithm that turns network requests into an API spec. This happens on device. Network requests are not sent to any servers, nor does the tool make any request or have need to.

To access the tool, open Firefox DevTools and find "OpenAPI" listed as a new tab. While DevTools is open and you select "Begin Recording", the tool receives a copy of each network requests in the HAR format. It then captures REST requests and dispatches them to the algorithm.

The algorithm converts these requests into a performant data structure that enables real-time generation of an OpenAPI 3.1 specification. New requests to the same endpoint are merged into the existing one.

You can specify path parameters in the settings menu. For example given the pathname "/api/posts/my-post", clicking on "my-post" will parameterise this part of the pathname, giving "/api/posts/:param2". This means that any request with a pathname matching "/api/posts/<anything>" will be merged into that endpoint.