"Wiring Source for Workspace Context"

If I select Other > Global Wiring Data in the Wiring tab for SOURCE PORTLET, a list is shown which contains the options “User Profile Wiring” and “Wiring Source for Workspace Context”.
The option “User Profile Wiring” is described in the “Administering My webMethods Server” documentation, but “Wiring Source for Workspace Context” is not explained anywhere. What is this option good for?