How can I add something to the heading part of HTML document with docutils
There is a meta directive to set meta tags if that's what you want.
If you are wanting to control the whole web page with your own css and javascript then you might want to look at Sphinx and write your own theme.
This document (http://docutils.sourceforge.net/docs/ref/rst/directives.html) explains about using .. raw:: to pass through HTML code in docutils, and the HTML code is in the body part of generated HTML.
How can I put something in heading part (..) with docutils?