AI Dictionary › Prompting

Lost in the Middle

"Lost in the middle" is the phenomenon where language models pay more attention to information at the beginning and end of a long context, and tend to overlook what sits in the middle. Even with wide context windows, a crucial fact buried halfway through a long document risks being ignored. Example: in a prompt with 30 paragraphs, the correct answer is in paragraph 15; the model answers poorly because that point got less weight than the first and last paragraphs.

Definition

Account for it when designing prompts with lots of context: put the most important instructions and data at the start or end, not the middle. In practice, reorder retrieved documents by relevance, repeat key instructions at the tail, or shrink context with compression and targeted retrieval instead of filling it.

Related terms

• Context Stuffing
• Needle in a Haystack
• Context Window
• Prompt Compression
• Context (in prompting)

More in Prompting

• Prompt
• Prompting
• Role Assignment
• Zero-shot
• Few-shot
• Chain of Thought
• Prompt Engineering
• Output Format

Put it into practice

• Real scenario: apply this concept with an instant AI verdict.
• Daily gym: short drills to train dictionary concepts.
• Playoff game: challenge other players, elimination-style.

📱 Download the Android app (beta) iOS coming soon

Say what you mean. Get what you need.

Grace Certified, the AI coach that trains and certifies your prompt engineering, by Agora Intelligence.