Agentic AI systems are increasingly capable of performing professional and personal tasks with limited human involvement. However, tracking these developments is difficult because the AI agent ecosystem is complex, rapidly evolving, and inconsistently documented, posing obstacles to both researchers and policymakers. To address these challenges, this paper presents the 2025 AI Agent Index. The Index documents information regarding the origins, design, capabilities, ecosystem, and safety features of 30 state-of-the-art AI agents based on publicly available information and email correspondence with developers. In addition to documenting information about individual agents, the Index illuminates broader trends in the development of agents, their capabilities, and the level of transparency of developers. Notably, we find different transparency levels among agent developers and observe that most developers share little information about safety, evaluations, and societal impacts. The 2025 AI Agent Index is available online at https://aiagentindex.mit.edu

翻译：自主AI系统日益能够在有限人类参与下执行专业及个人任务。然而，由于AI智能体生态系统复杂、迭代迅速且文档记录不统一，研究者与政策制定者均面临追踪此类发展的困境。为应对这些挑战，本文提出2025年AI智能体索引。该索引基于公开信息及与开发者的邮件沟通，记录了30个前沿AI智能体的来源、设计、能力、生态系统及安全特性信息。除记录单个智能体信息外，该索引揭示了智能体开发、能力及开发者透明度层面的整体趋势。值得注意的是，我们发现不同智能体开发者之间存在透明度差异，且多数开发者对安全措施、评估方法及社会影响的信息披露有限。2025年AI智能体索引在线访问地址为：https://aiagentindex.mit.edu