Benchmark Almanac

LoCoMo

GPT-3.5-turbo-16K (snapshot unspecified) 41.4% tops its leaderboard
Not in model cards

Models answer questions, summarize events and continue dialogue over very long multi-session chats of about 300 turns and 9K tokens, up to 35 sessions. Answers are scored against references.

Snap Research hosts the code and data on GitHub, with about 1,250 stars.

Released
February 2024
Kind
Finding facts in long inputs
Level
Everyday
Scored
Checked automatically
Answers
Short answer
Tasks
All public

In the authors’ words

Existing works on long-term open-domain dialogues focus on evaluating model responses within contexts spanning no more than five chat sessions. Despite advancements in long-context large language models (LLMs) and retrieval augmented generation (RAG) techniques, their efficacy in very long-term dialogues remains unexplored. To address this research gap, we introduce a machine-human pipeline to generate high-quality, very long-term dialogues by leveraging LLM-based agent architectures and grounding their dialogues on personas and temporal event graphs. Moreover, we equip each agent with the capability of sharing and reacting to images. The generated conversations are verified and edited by human annotators for long-range consistency and grounding to the event graphs. Using this pipeline, we collect LoCoMo, a dataset of very long-term conversations, each encompassing 300 turns and 9K tokens on avg., over up to 35 sessions. Based on LoCoMo, we present a comprehensive evaluation benchmark to measure long-term memory in models, encompassing question answering, event summarization, and multi-modal dialogue generation tasks. Our experimental results indicate that LLMs exhibit challenges in understanding lengthy conversations and comprehending long-range temporal and causal dynamics within dialogues. Employing strategies like long-context LLMs or RAG can offer improvements but these models still substantially lag behind human performance.

Abstract of Evaluating Very Long-Term Conversational Memory of LLM Agents (arXiv:2402.17753, CC0)
6
Entries on its own leaderboard, 0 models we track

GPT-3.5-turbo-16K (snapshot unspecified) tops the leaderboard with 41.4%

Best score per entry from the benchmark's own leaderboard, read on November 12th, 2026. Where a model ran with several settings or harnesses, we keep its best. Names in gray aren't in our model list: fine-tunes, agent systems, products and older models. They don't count toward leaders.

  1. 1 GPT-3.5-turbo-16K (snapshot unspecified) Observation top-5 41.4%
  2. 2 GPT-3.5-turbo-16K Long context, context 16K 37.8%
  3. 3 GPT-4-turbo (snapshot unspecified) Base, context 4,096 32.1%
  4. 4 GPT-3.5-turbo (snapshot unspecified) Base, context 4,096 22.4%
  5. 5 Llama-2-Chat-70B Base, context 4,096 17.9%
  6. 6 Mistral-Instruct-7B Base, context 8K 13.9%

Source: Official LoCoMo leaderboard

#EntryScoreSettingDateSource
1 GPT-3.5-turbo-16K (snapshot unspecified) 41.4% Observation top-5, DRAGON RAG Official leaderboard
2 GPT-3.5-turbo-16K 37.8% Long context, context 16K Official leaderboard
3 GPT-4-turbo (snapshot unspecified) 32.1% Base, context 4,096 Official leaderboard
4 GPT-3.5-turbo (snapshot unspecified) 22.4% Base, context 4,096 Official leaderboard
5 Llama-2-Chat-70B 17.9% Base, context 4,096 Official leaderboard
6 Mistral-Instruct-7B 13.9% Base, context 8K Official leaderboard

No lab model card reports it yet

We read the headline results of 522 launch posts from 52 labs, and none of them list this benchmark.

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