documentation format specifications

I've read the "Adding documentations to DevDocs" wiki page.
It explains how to use the scaper tool.
But I'd like to be able to build a documentation with my own tools.
Watching what is going through my web browser, I see an `/index.json` pointing to many HTML pages `/library/.html`.
Is it what I have to put in a PR under `devdocs/public/docs/` ?
How to provide the ToC, the icon, the description, the version ?