Is it possible to create a parameter which exists in all the part files in a project?
Which programming language are you using?
In Java and C++ you can create a class with all the variables defined as ‘public static’ and then you could have access to them from any file from the project. If you named the class Vars and a variable inside it var1 accessing it (in Java, I don’t remember C++ syntax sadly) would be
Vars.var1
This is for autodesk inventor.