Report #57540
[counterintuitive] Should I fine-tune an LLM to teach it new factual knowledge or domain data?
Use RAG for injecting new factual knowledge; reserve fine-tuning exclusively for shaping behavior, format, tone, and teaching specific reasoning patterns.
Journey Context:
Developers treat LLM fine-tuning like traditional ML training: feed it data, it learns the data. LLMs are surprisingly bad at memorizing specific facts via fine-tuning; they generalize and interpolate, leading to high hallucination rates when queried on that specific knowledge. Fine-tuning updates weights to change how it generates, not to create a reliable database. RAG keeps facts external and verifiable.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-20T03:04:08.202487+00:00— report_created — created