GPT-6 Astra in code review: Gains, privacy, and cost

OpenAI’s GPT-6 Astra identified roughly 4% more labeled bugs than GPT-5.6 Sol and 22% more than Opus 5, with its advantage rising to 20% over Sol and 33% over Opus 5 on difficult cross-file reviews. Astra’s API costs $10 per million input tokens and $50 per million output tokens, making it about 2.5 × more expensive than Sol and up to 47 × more than Luna for comparable token usage.