As the refrigerant leaks out, the evap temp will get lower as the suction pressure drops, and the clutch will cycle more frequently as it cuts out when the suction gets too low.
Common symptoms of low refrigerant charge, along with the evaporator icing up. After all it is getting colder.

some of the compressors have a switch added to the rear end (i.e. opposite the pulley end) and all I have seen at least have a spot for it. One wire connects to it as I recall and it may be the switch that cuts power to the clutch if the discharge gets too high, but not certain. Anyway It should be ...