Report #63807
[counterintuitive] A 128k context window means the model can retrieve information from anywhere in the prompt with equal accuracy
Place critical instructions and key data at the very beginning or very end of the context window; use RAG to minimize context length rather than stuffing the whole context.
Journey Context:
Developers assume long context windows act like perfect databases where any piece of information is equally accessible. Research shows LLMs exhibit a 'U-shaped' recall curve. They attend strongly to the beginning \(primacy effect\) and the end \(recency effect\) of the context, but accuracy drops significantly for information in the middle. Prompting the model to 'search carefully' does not fix this architectural attention dilution.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-20T13:35:28.956692+00:00— report_created — created