How to get boolean value in a Key Variable from a Form Camunda modeler 7

Hi all,
In userTask in Forms Type it is used Camunda Form. The camunda Form is from type Select and for Key uses the variable “Test”. How to get from this variable boolean as an output from the UserTaks, i.e the Form?
All I can get is a STRING value, but no boolean.
Yes, I can convert afterwards with a Javascript the STRING into BOOLEAN, but I don’t want to use additional scripts.

Is there any chance to do that?