An apparatus for operating on tissue includes an elongate shaft extending distally from a body and an end effector at a distal end of the elongate shaft. The end effector includes a first jaw that is selectively pivotable toward and away from a second jaw to capture tissue and a firing beam. The firing beam is configured to advance relative to the first and second jaws to sever captured tissue and retract relative to the first and second jaws after the captured tissue has been severed. The apparatus further includes a debris removal element in communication with the firing beam. The debris removal element is configured to engage at least a portion of the firing beam at least during retraction of the firing beam relative to the first and second jaws to thereby remove at least some debris from the firing beam.