Hmmm... in line 6 of plug-in A, the attribute value is set to an Integer and in line 1 of plug-in B the retrieved Integer value is cast to a String.
In fact, I have not clear if such a cast makes sense. Maybe, it is supposed to work, but to be surer, I would retrieve the value as an Integer and either use Integer.toString() in line 3 of plug-in B to convert it to a String or, if you feel lazy, rely in the implicit conversion:
I would prefer to first; also, chances are that sooner or later I'll need a more elaborate String.format() in the message to the player.
EDIT: Oh well, cross-posting...!