Repetition & novelty controls

frequency_penalty (-2 to 2)

Penalizes tokens proportionally to how often they have already appeared, reducing verbatim repetitions. Azure AI Foundry and OpenAI references document the range [-2, 2].

presence_penalty (-2 to 2)

Penalizes tokens that have already appeared at least once, nudging the model to introduce new topics. Azure AI Foundry and OpenAI references document the range [-2, 2].

Common patterns

• Reduce repetition in longer content: frequency_penalty ~ 0.2–0.8
• Encourage topic exploration in ideation: presence_penalty ~ 0.3–1.0

Caution: High penalties can degrade factuality or completeness.

Next: Length, Stops & Cost.