Select the methods you want to intercept and specify their interceptors.
If the Type to intercept its methods is an open generic type e.g.(MyClass <T>) you have to click this button to specify the type arguments the closed version(s) will use.
Generic Type Arguments
You should specify the generic type argument by their order. In this example we are specifying that we want to intercept methods on the the generic type ParserRuleReturnScope which has 2 generic arguments. We want to intercept on 2 closed generic variants. The first with <System.Int32, System.Boolean> and the latter with <System.Decimal, System.DateTime>.