AI 中文总结
研究长期智能体键值缓存内存问题，提出语义物化概念，通过实验发现精心措辞的无答案事件可提高恢复率，得出稀疏事件键值对服务的内存契约，指出丢弃源事件无准确性损失不代表其不必要。
AI 中文摘要
长期的智能体越来越多地将其键值缓存用作内存，即服务系统保留缓存条目的一个子集并丢弃其余部分。逐出和情景记忆方案基于一个很少直接测试的前提，即一旦产生某个事件的观测消失，保留的事件仍然具有信息性。我们通过在相同的智能体历史记录中省略一个早期观测来进行测试。在对该观测敏感的项目中，答案绝大多数遵循省略的值，尽管没有服务跨度表明哪个值是正确的。我们将此称为语义物化，即下游事件的缓存行充当其输入已消失的计算的可独立服务视图。它也可以有意编写。一个经过精心措辞、无答案的事件在Qwen3 - 8B上使捐赠者对齐的恢复率从6%提高到51%，而无需提及值，而从长期对话中被动收集自然提及则没有检测到优势。这样一行所承载的内容是特定且有界的。紧凑状态得以保留，较大的有效载荷趋向于随机会衰减，并且构造是否写入完全取决于措辞而非仅取决于含义，因此模型同样理解良好的两种措辞可能会有很大差异。结果是一个用于稀疏事件键值对服务的内存契约：写什么、写到哪里以及一旦源消失后什么会留存。对于任何进行逐出操作的人来说，推论是丢弃一个源事件且未观察到准确性损失并不表明该源是不必要的。
英文摘要
Long-horizon agents increasingly reuse their KV cache as memory: a serving system keeps a subset of cached entries and drops the rest. Eviction and episodic-memory schemes therefore rest on a premise rarely tested directly, that a retained event is still informative once the observations that produced it are gone. We test it by omitting one earlier observation from what is served, across otherwise identical agent histories. Among items sensitive to that observation, the answer overwhelmingly follows the omitted value, though no served span says which value is correct. We call this semantic materialization: a downstream event's cached rows act as an independently servable view of computation whose inputs are gone. It can also be written on purpose. A deliberately phrased, answer-free event raises donor-aligned recovery from 6% to 51% on Qwen3-8B without ever naming the value, whereas passively harvesting natural mentions from long-term dialog yields no detected advantage. What such a row carries is specific and bounded. Compact state survives, larger payloads decay toward chance, and whether a construction writes at all turns on phrasing rather than on meaning alone, so two phrasings the model comprehends equally well can diverge sharply. The result is a memory contract for sparse event-KV serving: what to write, where it lands, and what survives once the source is gone. For anyone who evicts the corollary is that dropping a source event and observing no accuracy loss does not show the source was unnecessary.
