Requirements

Below is a table of all requirements in PPDDL1.0. Some requirements imply others; some are abbreviations for common sets of requirements. If a domain stipulates no requirements, it is assumed to declare a requirement for :strips.

Requirement	Description
:strips	Basic STRIPS-style adds and deletes
:typing	Allow type names in declarations of variables
:equality	Support = as built-in predicate
:negative-preconditions	Allow negated atoms in goal descriptions
:disjunctive-preconditions	Allow disjunctive goal descriptions
:existential-preconditions	Allow exists in goal descriptions
:universal-preconditions	Allow forall in goal descriptions
:quantified-preconditions	= :existential-preconditions
	+ :universal-preconditions
:conditional-effects	Allow when and forall in action effects
:probabilistic-effects	Allow probabilistic in action effects
:rewards	Allow reward fluent in action effects and
	optimization metric
:fluents	Allow numeric state variables
:adl	= :strips + :typing + :equality
	+ :negative-preconditions
	+ :disjunctive-preconditions
	+ :quantified-preconditions
	+ :conditional-effects
:mdp	= :probabilistic-effects + :rewards