PrefEval: SOTA LLMs struggle to infer and follow user preferences in long conversations

math_rachel · x · 2026-10-19

The PrefEval paper (arXiv:2502.09597) evaluates LLMs' ability to infer, memorize and adhere to user preferences in multi-session long-context conversations. It contains 3,000 curated preference-query pairs across 20 topics (explicit and implicit), testing 10 open and proprietary models up to 100k tokens with various prompting, iterative feedback, and RAG methods. Findings: SOTA models struggle to proactively follow preferences — zero-shot accuracy drops below 10% at 10 turns (3k tokens) for most models, and fine-tuning on PrefEval significantly improves results.

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