ManagementCenter Hyperlink variables?

you can do it but not in the way that you thought.

For example you can set a hyperlink to address whatever camera is at this moment is in focus window. The API that you need i.e to play a sound on a camera is http://CamIP/control/rcontrol?action=sound&soundfile=Alarm (or the name of the file you want to play)

In the articles below you can find more infos about IP notify