Precondition-free STRIPS planning (source code)

= Precondition-free STRIPS planning

<Automated planning> with <ground actions> that are always applicable because their <precondition> sets are empty. Delete effects are still permitted, so taking the union of all add effects does not decide reachability. With a positive conjunctive goal, the <last-achiever algorithm for precondition-free planning> gives a <polynomial-time algorithm>.