How to use [io.folder.copy]

The reference page of io.folder.copy has its arguments, constraints and declaration.

Copies the specified source folder to its specified destination folder. Notice, this slot doesn’t copy the folder itself, but rather the folder’s content. Below is an example.

io.folder.copy:/misc/source-folder/
   .:/misc/destination-folder/

After invocation of the above, every single file and folder inside your “source-folder” can now be found as a copy inside your “destination-folder”.