PSOA RuleML API: A tool for processing abstract and concrete syntaxes PSOA RuleML is a rule language which introduces positional-slotted, object-applicative terms in generalized rules, permitting relation applications with optional object identifiers and positional or slotted arguments. This paper describes an open-source PSOA RuleML API, whose functionality facilitates factory-based syntactic object creation and manipulation. The API parses an XML-based concrete syntax of PSOA RuleML, creates abstract syntax objects, and uses these objects for translation into a RIF-like presentation syntax. The availability of such an API will benefit PSOA rule-based research and applications.