Thanks a lot for your answer and sorry for my delay reply. You were right it was pretty easy to make work this idea.
The approach that I followed was to create first a detail item family with 3 generic annotation famalies nested on it. These 3 nested families where associated to the 3 shared family parameters that I wanted to control with the run of each dynamo script : script name, user name and date time of the last run.
After this step I created the dynamo script by selecting the detail item family that I’ve just created it and pulling from dynamo "the script name"by using an string, "user name"by using a python script that you can find in the forum (http://dynamobim.org/forums/topic/get-the-revit-user-name/) and date/time of the run by using the node “DateTime.Now”
Finally I created and schedule showing these 3 parameters from the detail item family placed in the drafting view for having this information documented