Designers of agent communications protocols are increasingly using formal dialogue games, adopted from argumentation theory, as the basis for structured agent interactions. We propose a set of desiderata for such protocols, drawing on recent research in agent interaction, on recent criteria for assessment of automated auction mechanisms and on elements of argumentation theory and political science. We then assess several recent dialogue game protocols against our desiderata, revealing that each protocol has serious weaknesses. For comparison, we also assess the FIPA Agent Communications Language (ACL), thereby showing FIPA ACL to have limited applicability to dialogues not involving purchase negotiations. We conclude with a suggested checklist for designers of dialogue game protocols for agent interactions.

Negotiation is essential in settings where autonomous agents have conflicting interests and a desire to cooperate. For this reason, mechanisms in which agents exchange potential agreements according to various rules of interaction have become very popular in recent years as evident, for example, in the auction and mechanism design community. However, a growing body of research is now emerging which points out limitations in such mechanisms and advocates the idea that agents can increase the likelihood and quality of an agreement by exchanging arguments which influence each others ’ states. This community further argues that argument exchange is sometimes essential when various assumptions about agent rationality cannot be satisfied. To this end, in this article, we identify the main research motivations and ambitions behind work in the field. We then provide a conceptual framework through which we outline the core elements and features required by agents engaged in argumentation-based negotiation, as well as the environment that hosts these agents. For each of these elements, we survey and evaluate existing proposed techniques in the literature and highlight the major challenges that need to be addressed if argument-based negotiation research is to reach its full potential.

The Web Services world consists of loosely-coupled distributed systems which adapt to changes by the use of service descriptions that enable ad-hoc, opportunistic service discovery and reuse. At present, these service descriptions are semantically impoverished, being concerned with describing the functional signature of the services rather than characterising their meaning. In the Semantic Web community, the DAML Services effort attempts to rectify this by providing a more expressive way of describing Web Services using ontologies. However, this approach does not separate the domain-neutral communicative intent of a message (considered in terms of speech acts) from its domain-specific content, unlike similar developments from the multi-agent systems community. We describe our experiences of designing and building an ontologically motivated Web Services system for situational awareness and information triage in a simulated humanitarian aid scenario. In particular, we discuss the merits of using techniques from the multi-agent systems community for separating the intentional force of messages from their content, and the implementation of these techniques within the DAML Services model.

The theory of argumentation is a rich, interdisciplinary area of research straddling the fields of artificial intelligence, philosophy, communication studies, linguistics and psychology. In the last few years, significant progress has been made in understanding the theoretical properties of different argumentation logics. However, one major barrier to the development and practical deployment of argumentation systems is the lack of a shared, agreed notation or ‘interchange format’ for argumentation and arguments. In this paper, we describe a draft specification for an argument interchange format (AIF) intended for representation and exchange of data between various argumentation tools and agent-based applications. It represents a consensus ‘abstract model’ established by researchers across fields of argumentation, artificial intelligence and multi-agent systems. In its current form, this specification is intended as a starting point for further discussion and elaboration by the community, rather than an attempt at a definitive, all-encompassing model. However, to demonstrate proof of concept, a use case scenario is briefly described. Moreover, three concrete realizations or ‘reifications’ of the abstract model are illustrated.

A number of protocols based on the formal dialogue games of philosophy have recently been proposed for interactions between autonomous agents. Several of these proposals purport to assist agents engaged in the same types of interactions, such as persuasions and negotiations, and are superficially different. How are we to determine whether or not these proposals are substantially different ? This paper considers this question and explores several alternative definitions of equivalence of protocols.

Deliberation dialogues occur when two or more participants seek to jointly agree an action or a course of action in some situation. We present the first formal framework for such dialogues, grounding it in a theory of deliberative reasoning from the philosophy of argumentation. We further fully articulate the locutions and rules of a formal dialogue game for this model, so as to specify a protocol for deliberation dialogues. The resulting protocol is suitable for dialogues between computational entities, such as autonomous software agents. To assess our protocol we consider it against various records of human deliberations, against normative principles for the conduct of human dialogues, and with respect to the outcomes produced by dialogues undertaken according to the protocol.

Abstract. We describe the design of an intermediate language (AIL) for BDIstyle programming languages. AIL is not intended as yet another programming language, but is meant to provide a common semantic basis for a number of BDI programming languages in order to support both formal verification and the transfer of concepts and developments. We examine some of the key features of AIL, unifying a wide variety of structures appearing in the operational semantics of BDI programming languages. In particular, we highlight issues in the treatment of events, goals, and intentions, which are central to the design of these languages. 1

DALI [3] [2] is an Active Logic Programming Language designed in the line of [6] for executable specification of logical agents. A DALI agent is a logic program that contains a particular kind of rules, reactive rules, aimed at interacting with an external environment. The reactive and proactive behavior of the DALI agent is triggered by several kinds of events: external, internal, present and past events. All the events and actions are timestamped, so as to record when they occurred. The new syntactic entities, i.e., predicates related to events and proactivity, are indicated with special postfixes (which are coped with by a pre-processor) so as to be immediately recognized while looking at a program. The external events are syntactically indicated by the postfix E. When an event comes into the agent from its “external world”, the agent can perceive it and decide to react. The reaction is defined by a reactive rule which has in its head that external event. The special token:>, used instead of: −, indicates that reactive rules performs forward reasoning. The agent remembers to have reacted by converting the external event into a past event (time-stamped). Operationally, if an incoming external event is recognized,

What distinguishes e-commerce from ordinary commerce? What distinguishes it from distributed computation? In this paper we propose a performative theory of e-commerce, drawing on speech act theory, in which e-commerce exchanges are promises of future commercial actions, whose real-world meanings are constructed jointly and incrementally. We then define a computational model for this theory, called Posit Spaces, along with the syntax and semantics for an agent interaction protocol, the Posit Spaces Protocol or PSP. This protocol enables participants in a multi-agent commercial interaction to propose, accept, modify and revoke joint commitments. Our work integrates three strands of prior research: the theory of Tuple Spaces in distributed computation; formal dialogue games from argumentation theory; and the study of commitments in multi-agent systems.

Abstract. Current approaches to multi-agent interaction involve specifying protocols as sets of possible interactions, and hard-coding decision mechanisms into agent programs in order to decide which path an interaction will take. This leads to several problems, three of which are particularly notable: hard-coding the decisions about interaction within an agent strongly couples the agent and the protocols it uses, which means a change to a protocol involves a changes in any agent that uses such a protocol; agents can use only the protocols that are coded into them at design time; and protocols cannot be composed at runtime to bring about more complex interactions. To achieve the full potential of multi-agent systems, we believe that it is important that multi-agent interaction protocols exist at runtime in systems as entities that can be inspected, referenced, composed, and shared, rather than as abstractions that emerge from the behaviour of the participants. We propose a framework, called RASA, which regards protocols as first-class entities. In this paper, we present the first step in this framework: a formal language for specification of agent interaction protocols as first-class entities, which, in addition to specifying the order of messages using a process algebra, also allows designers to specify the rules and consequences of protocols using constraints. In addition to allowing agents to reason about protocols at runtime in order to improve their the outcomes to better match their goals, the language allows agents to compose more complex protocols and share these at runtime. 1