To have good judgment, taste, or the ability to appreciate fine details; to be discerning or discriminating.

to be discerning or tactful in noticing things and acting accordingly

(dialect) alert and attentive; able to see what needs to be done and doing it without being told

(colloquial) the ability to read situations and respond appropriately; sharp-eyed and quick to act

(informal) ability to read a situation and respond appropriately; being sharp-eyed or quick to see what needs to be done; tactful