This paper describes the software infrastructure introduced within the AgentService framework in order to provide support for ontology design, development, and management. Ontology enriches and normalizes the interaction among agents by establishing a domain and a set of relation among objects populating that domain. A good support for ontology definitely adds value to the design and the implementation of software agents: software engineers can take advantages of the services offered by the framework to produce new ontologies and rely on them to quickly define interaction protocols which are automatically translated into state machines used by software agents.