Slate is an option for generating static documentation for API. You can fork it. You can clone the forked repo. It uses redcarpet for syntax highlighting. The index markdown page shows how you can specify the tabs for the languages, footers and searching. It shows a sample document that you can use as a starting point. You need to run bundle to install the gems. You can then run the server with this command. We can now browse the documentation. You can customize this by replacing the book with your logo. You can see sample code for different languages in the tab. You can see the error codes. We can play with the API using curl in the command line. It also has a search feature. You can also have link to developer signup. API Blueprint is another option. You can document your API using markdown. You can refer the documentation at API blueprint website for the tutorials and reference. Once you document your API using blueprint, you can use aglio to generate the html documentation for your API. The three column layout is appealing. It is easy to browse the documentation and find the details about the request, response, headers and parameters. I will be discussing about this in more detail in the next paid episode.
Api Blueprint Document Generator
Swagger Sinatra Example
Streamlining API with Swagger
API Blueprint Examples