How do can I use custom context parameters in a atlassian-connect.json page url?

I’m aware of, Section “Add-on specific context parameters”. I understand how I receive those parameters when an application calls my addon. But how do I set them?

I need to know which version of my addon a user is using after a version change. Or is there another way I can obtain this information?

@m22, Did you figure out how to set them? I’m also puzzled by this.