The main panel in the plugin is the Sweep panel. All the available sweepers are displayed here. If the sweeper has nothing to sweep, it will be hidden by default. The same is for individual sweepers, if the sweeper has some tasks without anything to sweep, they will be hidden.
Each sweeper has additional controls to show empty tasks, show help, and limitations. You can see all that in the example image below.
Each sweeper includes detailed information about the data it will remove, how that relates to the database structure and why you should use it in the first place. Some sweepers have limited scope of use and recommendation on how to use them, so it is very important to check all provided information to understand better the whole process.