We introduce Memento, a conversational AR assistant that permanently captures and memorizes user's verbal queries alongside their spatiotemporal and activity contexts. By storing these "memories," Memento discovers connections between users' recurring interests and the contexts that trigger them. Upon detection of similar or identical spatiotemporal activity, Memento proactively recalls user interests and delivers up-to-date responses through AR, seamlessly integrating AR experience into their daily routine. Unlike prior work, each interaction in Memento is not a transient event, but a connected series of interactions with coherent long--term perspective, tailored to the user's broader multimodal (visual, spatial, temporal, and embodied) context. We conduct preliminary evaluation through user feedbacks with participants of diverse expertise in immersive apps, and explore the value of proactive context-aware AR assistant in everyday settings. We share our findings and challenges in designing a proactive, context-aware AR system.

翻译：我们介绍了Memento，一种会话式AR助手，它能永久捕获并记忆用户的口头查询及其时空与活动情境。通过存储这些“记忆”，Memento能够发现用户反复出现的兴趣点与触发这些兴趣的情境之间的关联。当检测到相似或相同的时空活动时，Memento会主动唤起用户的兴趣，并通过AR提供最新的响应，从而将AR体验无缝融入用户的日常生活。与先前工作不同，Memento中的每次交互并非孤立事件，而是基于用户更广泛的多模态（视觉、空间、时间与具身）情境，形成具有连贯长期视角的交互序列。我们通过收集不同沉浸式应用专业背景参与者的用户反馈进行了初步评估，并探讨了主动情境感知AR助手在日常环境中的价值。我们分享了在设计主动情境感知AR系统过程中的发现与挑战。