Our project aims at the automatic generation of multilingual text for product maintenance and documentation from a structured knowledge representation formalized by means of plans in a description logic. These plans consist of one or more actions or other plans. This language independent representation is also designed to support the qualitative simulation of the documentation steps and to support the generation of multilingual text by o ering action descriptions at di erent levels of detail for verbalization. This requires a hierarchical organization of performable action descriptions capable to de ne actions by inheriting already existing actions. Prerequisite for inheritance of pre- and postconditions of actions in a KL-ONE system is the de nition of a proper subsumption relation for this logical expressions, conform with the subsumption for ordinary KLONE constructs. We propose a framework for extending the Loom system with syntax and semantics for representing and reasoning with ...