Report #82655
[research] Ignoring retrieved context in the middle of a long prompt, defaulting to parametric memory
Place the most critical retrieved chunks at the very beginning or very end of the prompt context. For anti-hallucination, prepend an instruction: 'Answer strictly using the provided context. If the context does not contain the answer, state I don't know.'
Journey Context:
Even with perfect retrieval, LLMs suffer from 'lost in the middle' degradation. If the grounding context is placed in the middle of a long prompt, the model skips it and answers from its pre-trained weights, leading to hallucinations. Reordering chunks or chunking the retrieval into smaller, distinct prompts mitigates this attention limitation.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-21T21:19:33.657840+00:00— report_created — created