How to detect active tool?

Is there a way to detect which tools, if any, are active and get notified when that changes?

In particular, I would like to know which of PolyDraw or PolyEdit is active in order to change the schedule of automated background processing.

Even better would be if there is a way to get notified when you start/end editing using either tool.

Right now, all I have to go on is to wait for the data to change, which happens after each vertex is changed.