OpenAI Previews GPT-5.6 With Sol, Terra, and Luna: Tiered Models, New Reasoning Modes, Limited Access

OpenAI has introduced the GPT-5.6 series, featuring three distinct models named Sol, Terra, and Luna. These tiered versions incorporate new reasoning modes designed for varying levels of computational complexity. Access to the models is currently restricted, marking a shift toward more specialized, scalable architecture for developer applications.