Edit or add. That's the primary instruction. You can edit directly on `gitlab.com/agaric/documentation <https://gitlab.com/agaric/documentation>`_ (for example, the edit link on this page takes you to `gitlab.com/agaric/documentation/blob/master/documentation.rst <https://gitlab.com/agaric/documentation/blob/master/documentation.rst>`_). If you aren't a member of Agaric, GitLab will helpfully offer to fork the documentation to your own namespace so that you can make a merge request with your documentation suggestion.
This documentation page is a good one to copy or refer to as an example for ReStructuredText formatting. And of course anyone can come and clean up formatting later.
In documentation we are living our `values <values>` of encouraging continuous learning, appreciating new ideas, giving back to the communities we are part of, and valuing long-term relationships.