The smart 451 both petrol and diesel have a semi automatic gearbox, this means it has a mechanical setup but it uses actuators to move the mechanical parts based upon driver input ie changing gear.
To manually adjust the clutch “bite point” you have to relearn the ECU values and adjust the physical actuator.
By moving the actuator closer to the clutch you are increasing the bite point over time the clutch because worn and “loose” you may notice jerky or higher revs when changing gear this is a good indication that you will either have a worn clutch or need actuator.