Agents Through the Ages

Abstract

Abstract Over several decades, research on socially interactive agents has transformed human–machine interaction, evolving from early script-based systems to today’s generative, multimodal agents. Tracing this development through the ages, this article reflects on major conceptual and technical shifts that shaped the field, drawing on advances across multiple areas of AI, and discusses how progress in natural language processing and multimodal behavior analysis and generation has redefined AI as a social interface. Rather than presenting this trajectory as a narrative of continuous progress, we also examine persistent limitations, including weak grounding, difficult evaluation, opaque decision processes, safety risks in sensitive contexts, and the gap between convincing social simulation and genuine social understanding.