I haven't understood the exact scenario you were asking about method to find the activity.
In case if you are looking for the calling rule, you may open the activity and Under other Actions button, click on view references to find the rules that are referring to this activity. In run time, you can use tracer to find it.
If you can do a private-check-out of the called Activity ; you could add in something like this (Java Step):
Exception e =new Exception("debug");
java.io.StringWriter writer = new java.io.StringWriter();
java.io.PrintWriter pw = new java.io.PrintWriter(writer);
String trace = writer.toString();
oLog.infoForced( trace );
Which will dump the current Java Call Stack: which should help you identify what called the Activity in each particular case.
You get something like this ('dumpStack' is the name of my test Activity - it will be different of course in your case).
2017-02-14 11:50:26,757 [ttp-bio-7220-exec-32] [ STANDARD] [ ] [ GCS:01.01.01] (mpStack.OBQ6DY_GCS_Work.Action) INFO xxxxx|10.4.42.78 Admin@GCS - java.lang.Exception: debug
You mentioned sla and user-local-action. If your need is merely to know whether you are in an sla context or not, take a look at one of the parameters that gets passed during sla context. I believe there's a parameter that indicates specifically whether we're in an sla context or not. /Eric