Unless I’ve missed it, there doesn’t seem to be a way to set “required” variables for a graph. Or, variables that are required to be set in the variables component for a graph to work that are auto-added on new instances of the graph.
An example of this would be making a macro script machine, setting your object variables names/type/value, and building your graph. And then using this macro on another object, but when you add the graph, the variables set is empty - requiring you to re-add your object variables, which is a moderately complicated graph, can be taxing. You can create a preset of the variables, or copy/paste the values from one object to another - but it seems logical to all have this done for you, saving time.
Proposed change: When adding an object variable to a graph on the blackboard, give an option to also set the variable to be required or auto-added anytime this graph is added to an object - with a default value/type supplied.