OpenAI's GPT-5.6 family — Luna ($1/$6), Terra ($2.50/$15), Sol ($5/$30) — hits GA. Sol beats Claude Fable 5 on Agents' Last Exam by 13.1 points.
Windsurf's changelog adds a model labeled GPT-5.4 with four reasoning tiers at 1x–3x credit costs. Here's what the listing says and how to use it.