GPT-5.6 Luna is 28x cheaper than GPT-6 Astra, but less secure.
Luna detected 75% of Astra’s bugs (in 50 pull requests) at 3.6% the cost. Luna found 9 out of 24 security vulnerabilities compared to Astra finding 19 out of 24.
Luna (GPT-5.6) identified 69 actual bugs across 50 pull requests, while Astra (GPT-6) identified 92 actual bugs across 50 pull requests. The precision for Luna was 74%, whereas the precision for Astra was 96%. Running Luna costs $0.20, but running Astra costs $5.66 — that’s a 28x price difference!
This means that we can achieve 75% of the performance of Astra at a fraction of the cost. But when it comes to critical sections of code such as authentication and authorization, only 9 out of 24 security issues were identified by Luna, versus 19 out of 24 identified by Astra. In these cases, I wouldn’t compromise on using a higher quality model.
Source: entelligence.ai
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Author
Evgenii Arsentev
PhD · Chief Executive Officer, digital health
Articles · Latest articles