I have a scheduled agent that runs Weekly at one particular time on a target of All new & modified documents.
If I modify this agent, even if I only save it, it runs again.
If I remember correctly from long long ago, I have to add code such as this:
Dim db As NotesDatabase
Dim agent As NotesAgent
Set db = s.CurrentDatabase
Set agent = db.GetAgent("myAgent")
If agent.HasRunSinceModified = False
Exit Sub
End If
Am I remembering correctly? And I always wondered, why would an agent fire off after being modified? Makes no sense to me.
My response corresponds to your title: Preventing Scheduled Agent from executing when modified.
The solution is to move all your code to a script library, and never change the agent (since no need of it).
When you modify your code in the script library the agent is not fired.
You can also read Notes Designer runs agent after saving which suggest (I didn't test) Amgr_SkipPriorDailyScheduledRuns=1