Heterogeneous Active Agents, I: Semantics

Over the years, many different agent programming languages have been proposed. In this paper, we propose a concept called Agent Programs using which, the way an agent should act in various situations can be declaratively specified by the creator of that agent. Agent Programs may be built on top of arbitrary pieces of software code and may be used to specify what an agent is obliged to do, what an agent may do, and what an agent may not do. In this paper, we define several successively more sophisticated and epistemically satisfying declarative semantics for agent programs. We further show that agent programs cleanly extend well understood semantics for logic programs, and thus are clearly linked to existing results on logic programming and nonmonotonic reasoning. 1Institut und Ludwig Wittgenstein Labor für Informationssysteme, Technische Universität Wien, Paniglgasse 16, A-1040 Wien, Austria. E-mail: [email protected] 2Institute for Advanced Computer Studies, Institute for Systems Research and Department of Computer Science, University of Maryland, College Park, Maryland 20742. E-mail: [email protected] 3Department of Computer Science, University of Maryland, College Park, Maryland 20742. E-mail: [email protected] Acknowledgements: We wish to thank Alex Dekhtyar, Jürgen Dix, Sarit Kraus, Munindar Singh, Terrence Swift, and others for a very close reading of previous versions of this manuscript, and for the numerous detailed comments they made. These comments have significantly improved the quality of this paper. We have also benefited from discussions with Swati Allen, Piero Bonatti, Steve Choy, Phil Emmerman, Dana Nau, Anil Nerode, Dino Pedreschi, and Jose Salinas. This work was supported by the Army Research Office under Grants DAAH-04-95-10174, DAAH-04-9610297, and DAAH04-96-1-0398, by the Army Research Laboratory under contract number DAAL01-97K0135, by an NSF Young Investigator award IRI-93-57756, and by a DAAD grant. his work was initiated by R. Stewart. This is Part I of a revised and extended version of the Technical Report UMCP-CSD CS-TR-3880, “Heterogeneous Active Agents”, Computer Science Department, University of Maryland. Copyright c 1999 by the authors INFSYS RR 1843-98-02 I