Instructions for making menu items for plugins

Hello

I am writing a plugin for KOReader but I'm struggling to figure out

1. how to add settings for the plugin in the tools menu at the top of the KOReader UI

2. how to add an item in the long press menu in the file picker

I tried to have a look at the dev docs but the pages for apps.filemanager.filemanagerutil and ui.widget.touchmenu seem empty?

Thanks