Story
If I select an item, Magnolia provides me with a preview of the item as well as the list of common actions applicable to it. I can also retrieve a list of all actions defined on the currently selected item, if I choose so, but it's the common actions which are visible by default.
Magnolia also offers me additional information on the item that might be available, if this makes sense in the current context. I could get a list of users working on a page in a interface showing me the status of work items. Or I could get access to a page's history to check out the changes applied to it in the last 24 hours.