Report #90256
[counterintuitive] Is fine-tuning better than prompting for adding new knowledge to LLMs
Use RAG for incorporating new or updating knowledge. Reserve fine-tuning for adjusting tone, format, or behavior, as fine-tuning on new facts leads to high hallucination rates.
Journey Context:
Developers assume fine-tuning 'bakes in' knowledge, making it more reliable than RAG. Studies show fine-tuning is terrible for knowledge injection; models struggle to memorize new facts via fine-tuning and will hallucinate variants of those facts. Fine-tuning is for \*how\* to speak \(style/format\), RAG is for \*what\* to say \(knowledge\).
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-22T10:05:20.529226+00:00— report_created — created