long-term-memory CAP-0030 · activeRemembering across sessions
Assistants fail to recall and apply facts, preferences, and decisions from earlier sessions.
Also called: persistent memory, cross-session memory, personalization
Tags: autonomous-agent, chat-assistant, context, customer-support
A capable assistant carries forward what a user told it and what was decided, notices when a stored fact has changed, and reasons over information spread across many past interactions.
Claims
- mechanismsingle paper↑1↓0Commercial assistants show a large accuracy drop when the relevant information sits in a long interaction history, especially for updates and multi-session reasoning.
- mechanismsingle paper↑1↓0For conversational long-term memory with 8-14B backbones and plain top-K dense retrieval, writing each dialogue span into several complementary low-overlap semantic views before indexing retrieves gold evidence for more queries than structured extraction into a single view, and the advantage is largest at small retrieval budgets.
- mechanismsingle paper↑1↓0A memory stream with retrieval and reflection lets agents behave consistently over simulated days.
- observationsingle paper↑1↓0On multi-year authentic personal photo/video archives turned into memory streams, frontier multimodal models and structured memory systems recall facts and infer persona far better than they predict a user's future choices: predicting or recommending in novel contexts caps around 59 on a 0-100 scale for every system tested, and compressing the history ~70x into a memory system costs nothing on that tier while costing a lot on factual recall, so predictive personalization is limited by preference representation rather than by retrieval or context length.
- mechanismsingle paper↑1↓0For persistent-memory agents, any memory-write rule that decides using only recency and provenance is stuck on a single tradeoff — accepting more genuine preference updates means admitting more poisoned ones — because an adversary who can launder a claim through the user's own channel matches the statistics a genuine revision produces; conditioning the write decision on the inferred authenticity of the claim given the interaction history moves both axes at once.
- observationsingle paper↑1↓0When the preference needed to answer a query lies in a different concept space from the cues in a user's dialogue history (e.g. inferring an emotion-regulation strategy from personality cues), retrieval-based and profile-summarization personalization methods barely beat a no-history baseline, and dumping the full history into the prompt does worse than no history at all.
- mechanismmechanism reasoning↑2↓0A running summary buys continuity across a long conversation at the cost of specifics, because it is lossy compression by construction — so it helps with "what were we doing" and not with "what exactly did I say in turn 40." Keeping the raw turns retrievable alongside the summary covers the second case.
- mechanismsingle paper↑1↓0Recursively summarizing the dialogue into a running memory improves consistency in long conversations.
- observationsingle paper↑1↓0In retrieval-augmented personalization with a frozen 8-9B generator, prepending more retrieved user-history records does not monotonically improve quality — on the six LaMP tasks a fixed top-k profile peaked at k=5 and lost 0.8 quality points at k=10 while the share of cases made worse than an empty profile rose from 23.2% to 31.7% — so a learned per-request stopping decision beats any single fixed k.
- observationsingle paper↑1↓0When a structured long-term memory substrate (indexes, retrieval, control logic) is held fixed and only the backbone LLM is swapped, accuracy on multi-session memory benchmarks like LongMemEval and LoCoMo moves by a few points while per-query cost varies by roughly an order of magnitude, so recall quality in these settings is set mostly by the memory and retrieval design rather than by model choice.
- mechanismsingle paper↑1↓0A tiered memory system managed by the model itself sustains recall over conversations far longer than the context window.
Techniques
- Checkpoint task state to a fileprocessWrite task id, status, completed steps and artifact paths to a small file after every meaningful step, and read it at session start.
- Maintain a running summarypromptingPeriodically fold the conversation into a summary that replaces older turns.
- Tiered memory managed by the modelarchitectureKeep a small working context and let the model page facts in and out of external storage.
- Weight profile attributes by temporal stabilitypromptingDistil a structured user profile incrementally from history, score each attribute by support, duration and recency combined with entropy weighting, and inject the score as a salience prior in the prompt.
- Write memory into self-configured orthogonal viewsretrievalInduce candidate schemas (views) from the interaction stream, pick a diverse subset by DPP, extract provenance-tagged memories under each view before indexing, then consolidate duplicates offline.
Sources
Every paper, post or observation behind this capability. Ones cited by a claim show the claim and its stance; ones filed directly are about the capability but have no claim drafted from them yet. Open one to add support or contest it.
- ↑ supports a claim here
- about this capability · no claim drafted yet
- ↑ supports a claim here
- Less Is Personal: Learning Minimal Sufficient User Profiles for Personalized Language Models2026-09-08↑ supports a claim here
- ↑ supports a claim here
- VIBE-Bench: Evaluating Personalized Large Language Models When Profiles Don't Mean Preferences2026-09-01↑ supports a claim here
- ↑ supports a claim here
- about this capability · no claim drafted yet
- LongMemEval: Benchmarking Chat Assistants on Long-Term Interactive MemoryThis source: LongMemEval: Benchmarking Chat Assistants on Long-Term Interactive Mem…How much the field cites it — very heavily cited in the last 12 months517 in the last 12 months · 588 totalpublished 2024checked 2026-09-042024↑ supports a claim here · ↑ supports a claim here
- Generative Agents: Interactive Simulacra of Human BehaviorThis source: Generative Agents: Interactive Simulacra of Human BehaviorHow much the field cites it — very heavily cited in the last 12 months1000+ in the last 12 months · 5387 totalpublished 2023checked 2026-09-04count capped at 1000 by the fetchclick for Semantic Scholar2023↑ supports a claim here
- Recursively Summarizing Enables Long-Term Dialogue Memory in Large Language ModelsThis source: Recursively Summarizing Enables Long-Term Dialogue Memory in Large Lan…How much the field cites it — heavily cited in the last 12 months51 in the last 12 months · 93 totalpublished 2023checked 2026-09-042023↑ supports a claim here · ↑ supports a claim here
- MemGPT: Towards LLMs as Operating SystemsThis source: MemGPT: Towards LLMs as Operating SystemsHow much the field cites it — very heavily cited in the last 12 months984 in the last 12 months · 1246 totalpublished 2023checked 2026-09-04click for Semantic Scholar2023↑ supports a claim here
Capabilities are a way of carving up the subject, and carvings are arguable. Say so if this one is wrong — especially a proposed one, which a pipeline added because several papers used the same framing, not because anyone decided it was right.