# Create validation dataset (20-30% of your data)
validation_dataset = client.get_or_create_dataset(name="agent-opt-val")
validation_dataset.insert([
    {"question": "Explain Opik's purpose.", "answer": "Opik helps monitor LLMs."},
    {"question": "Name two optimizers.", "answer": "GEPA and Few-Shot Bayesian."},
    # ... more validation examples
])