Signifiers as a First-class Abstraction in Hypermedia Multi-Agent Systems

Hypermedia APIs enable the design of reusable hypermedia clients that discover and exploit affordances on the Web. However, the reusability of such clients remains limited since they cannot plan and reason about interaction. This paper provides a conceptual bridge between hypermedia-driven affordance exploitation on the Web and methods for representing and reasoning about actions that have been extensively explored for Multi-Agent Systems (MAS) and, more broadly, Artificial Intelligence. We build on concepts and methods from Affordance Theory and Human-Computer Interaction that support interaction efficiency in open and evolvable environments to introduce signifiers as a first-class abstraction in Web-based MAS: Signifiers are designed with respect to the agent-environment context of their usage and enable agents with heterogeneous abilities to act and to reason about action. We define a formal model for the contextual exposure of signifiers in hypermedia environments that aims to drive affordance exploitation. We demonstrate our approach with a prototypical Web-based MAS where two agents with different reasoning abilities proactively discover how to interact with their environment by perceiving only the signifiers that fit their abilities. We show that signifier exposure can be inherently managed based on the dynamic agent-environment context towards facilitating effective and efficient interactions on the Web

Agents on the Web (Dagstuhl Seminar 23081)

Recent standardization on the Web of Things and (Social) Linked Data unlocks new practical use cases and new opportunities for research on Web-based multi-agent systems. While existing research on multi-agent systems can contribute to engineering adaptive and flexible Web-based systems, increased deployment of systems following the recent standards can bring new insight into engineering large-scale and open multi-agent systems. These developments motivate the need for a broader perspective that can only be achieved through a concerted effort of the research communities on Web Architecture and Web of Things, Semantic Web and Linked Data, and Autonomous Agents and Multi-Agent Systems. Thus, the main objective of the Dagstuhl Seminar 23081 on Agents on the Web was to investigate these new research opportunities, to support the transfer of knowledge and results across the different communities, and to create a network of leading scholars and practitioners around these topics. This report documents the seminar’s program and outcomes. To continue the joint work after the seminar, the seminar participants created the W3C Autonomous Agents on the Web (WebAgents) Community Group