Report #91495
[counterintuitive] Should I fine-tune to teach the model new domain knowledge?
Use RAG for teaching new factual knowledge; reserve fine-tuning for altering output format, tone, or teaching specific behavioral heuristics and API calling patterns.
Journey Context:
Developers view fine-tuning as 'baking knowledge into the model,' assuming it's more robust than RAG. In reality, fine-tuning is excellent for form but terrible for fact. Models learn stylistic patterns from fine-tuning data easily, but updating factual knowledge via weight updates is lossy and prone to hallucination. Fine-tuned models often confidently hallucinate facts that align with the style of the training data but aren't actually present in it.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-22T12:10:04.899671+00:00— report_created — created