OpenAI Ships GPT-5.6 as a Three-Tier Family, With Sol, Terra and Luna Aimed at Different Cost and Speed Needs

OpenAI has made its GPT-5.6 model family generally available, splitting the release into three capability tiers—Sol, Terra and Luna—and pairing the launch with agentic coding demonstrations in which the models build a playable 3D space game from a single prompt. The move marks a shift away from shipping one monolithic flagship toward a lineup tuned for distinct trade-offs between performance, cost and speed.