Yes Workflows offer a variety of call backs do you not have Builder/CSIDE documentation?
Main classes are=General Call backs-step entered,step exited,workflow started/stopped/archived/deleted etc
Performer Call backs
Submap call backs
Usually much easier to do than regular lliapi node call backs
If OT documentation does not get you started I have written things about 7/8 years back in communities
a free developer site that OT retired
the first link should get you with stuff that I wrote .
Note I wrote that for old livelink systems but oscript has not changed

Code That I wrote in oscript in 2000 I can still use in 2015....
Well, if I called the wrong number, why did you answer the phone?
James Thurber, New Yorker cartoon caption, June 5, 1937
Certified OT Developer,Livelink ECM Champion 2008,Livelink ECM Champion 2010