New model options in Agent Builder

New in Agent Builder: OpenAI's GPT-5.6 models. GPT-5.6 ships as three tiers - not one model - so you can match the model to the job. Sol is our most capable tier, built for demanding coding and analysis. Terra delivers balanced everyday performance at a lower cost. Luna is fast and lightweight for high-volume, simpler tasks. Pick any of them from the model picker when you configure an agent. All three run in standard (instant) mode today; reasoning/thinking mode is not available for these models yet and is planned for a future update. Cost note: after a recent OpenAI price cut, Luna is now our most cost-efficient model option - roughly 5x cheaper than Claude Haiku on both input and output - making it a great pick for high-volume, lower-complexity work where you would previously have reached for Haiku.