Before you start
- An instance of Luna Studio deployed for your org (Luna Studio is part of the enterprise tier — see Availability and deployment).
- An email address for the Luna Studio account.
- An API key for at least one supported LLM provider: OpenAI, Anthropic, Google AI Studio, or Groq.
- A labelled CSV test dataset with the columns your metric requires, at least 300 rows total, and at least 100 examples per class. The source picker can ingest JSONL, but current run processing requires CSV.
- Optional for training, required for import and registration: a Galileo API connection configured by your Luna Studio deployment operator.
Walkthrough
Sign up

Create a Luna Studio account
Connect your first LLM provider
Create your first project
support-tone-classifier). Click Continue again — Luna Studio creates the project and routes you to its Training runs page.
Onboarding, step 2 — name your first project
Start a new training run
Pick a metric (Step 1)
Add a test set (Step 2)

New run, Step 2 — pick or upload a test set to evaluate against
label column. Because you are adding the dataset inside the run wizard, Luna Studio runs metric-aware validation before attaching it to the run. Resolve any highlighted errors before continuing.Click Next step.Add a training set (Step 3)
- Generate from test set (recommended for a first run) — Luna Studio uses 20% of your test set as seed examples and targets 2,000 synthetic labelled examples using your LLM-as-judge prompt from Step 1. Enhancement examples can be appended, so the final row count may be higher.
- Add training logs — upload or import your own production logs.
- Use existing training set — reuse a training dataset that already exists in your workspace. If you pick Generate, a drawer opens. Pick a model from your configured providers and click Generate sample dataset. Data generation moves through Queued → Generating data → Data ready inside Step 3. Review the sample rows, select any that should steer regeneration, and click Generate final dataset. Wait for the final dataset to be ready before continuing. Click Next step.
Confirm and launch (Step 4)

New run, Step 4 — pick a base model and launch fine-tuning
Wait for training to complete

Run details for a fine-tuned run, ready to register
Register your metric