How to make component props default data available to Plasmic Studio only?

hi, I am using CodeGen in Plasmic and would like to know how to make Component props default data to be available in Plasmic Studio only?
I see that you have 3 types of props: External , Internal and Tools Only. Both External and Internal will make the default prop value which is meant to style the Component in Plasmic Studio to be generated with Code Gen.
Tools Only will make the default value NOT generated by Code Gen but it’s not showing up inside Plasmic Studio Dynamic value as well.

can you advise? Thanks a lot