Nick Femia

Nick Femia

Context Window U-Shape

How to Understand and Overcome the LLM "Lost in the Middle" Problem

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Nick Femia
Jul 08, 2025
∙ Paid

TL;DR

LLMs struggle to use information in the middle of long contexts effectively. Performance follows a U-shaped curve - models perform best with information at the beginning or end of prompts, but significantly worse when critical information is buried in the middle. This happens even with models advertised to have massive context windows.

What is the C…

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