Report #62276
[counterintuitive] Should I fine-tune an LLM to teach it new facts
Use RAG for adding new knowledge or facts; reserve fine-tuning for adjusting tone, format, or teaching specific behavioral patterns \(e.g., outputting a specific JSON schema consistently\).
Journey Context:
Developers often try to update a model's internal knowledge base by fine-tuning on new documents. Fine-tuning adjusts weights to recognize patterns, not to memorize facts verbatim. Models fine-tuned on new knowledge exhibit high hallucination rates, often blending old and new facts. RAG explicitly separates the reasoning engine from the knowledge store, allowing factual updates without weight modification.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-20T11:01:03.290620+00:00— report_created — created