A surgical tool including a lockout mechanism is provided. The surgical tool may include an instrument mounting portion including a shaft assembly coupled to and extending distally from the instrument mounting portion and an end effector including a reciprocatable element coupled to a distal end of the shaft assembly. The surgical tool may further include an energy source configured to deliver energy to the end effector and an actuation mechanism configured to actuate the end effector. The actuation mechanism may be configured to reciprocate the reciprocatable element of the end effector. The lockout mechanism may be operably interfaced with the actuation mechanism to control reciprocating movement of the reciprocatable element.