Skip to content
BytePatterns

Fine-Tuning vs Prompting

AI & ML: lesson 13 of 32

Change the instructions, or change the weights.

Lesson 13 of 32 · 5 min

Fine-Tuning vs Prompting

Step 1 of 13

Prompting steers a frozen model with instructions supplied at request time.

The Idea

Prompting steers a frozen model with instructions and examples supplied at request time. Fine-tuning continues training on your own examples so the behaviour is baked into the weights. One is instant and reversible; the other is neither.

Real-World Example

Airline cabin crew. The safety card is read out every flight and can be reprinted overnight. Recurrent training reshapes reflexes instead — weeks of work, and no memo can undo it by tomorrow.

The Tradeoff

Fine-tuning buys consistent formatting, shorter prompts and lower cost per call. It charges you dataset curation, a training run, and a model version to maintain and redo on every base-model upgrade. Prompting and retrieval are almost always the cheaper first attempt.

Your turn

Put the steps in the right order.

  1. Fine-tune on curated examples, but only if the gap survives everything above
  2. Write a clear prompt with a few worked examples
  3. Add retrieval if the failures turn out to be missing facts
  4. Measure where the output actually falls short

Mini quiz

1 / 3

Fine-tuning is best suited to:

New lessons land every few weeks

Leave an address and we will tell you when the next one is up. That is the only reason we will use it.

One address, stored so we can email you. Nothing else, ever.