Done merely to get rid of a duty; performed mechanically and as a thing of rote; done in a careless and superficial manner; characterized by indifference; as, perfunctory admonitions.

Hence: Mechanical; indifferent; listless; careless.

hasty and without attention to detail; not thorough; "a casual (or cursory) inspection failed to reveal the house's structural flaws"; "a passing glance"; "perfunctory courtesy"

as a formality only; "a one-candidate pro forma election"

done without care or concern