Which GPT-6 model should you use for AI engineering workflows?
OpenAI's GPT-6 docs split the family on an operational boundary before quality even enters the picture: GPT-6 Astra and GPT-6.1 Sol do not support `none` reasoning effort, while GPT-6 Luna does. Start with Luna for bounded, high-volume work, move to GPT-6.1 Sol for complex tool-driven flows, and use Astra only when measured task quality still misses the bar.
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