purposeless

Synonyms: aimless designless desultory drifting empty feckless floundering fustian goalless good-for-nothing haphazard hit-or-miss indiscriminate irregular meaningless motiveless needless nonsensical pointless purportless random senseless uncalled for undirected unhelpful unnecessary unplanned unprofitable unpurposed vacuous wanton worthless

Antonyms: decided deliberate determined planned purposeful significant useful