GPT 5.6 Has 72 Possible Configurations. What's A Good Default?

This article explores the overwhelming number of configuration options in the GPT 5.6 release, which offers 72 possible combinations across model size (Sol, Terra, Luna), reasoning effort levels (Light to Ultra), and settings like Work/Codex and Standard/Fast. It discusses how these choices relate to training-time and inference-time scaling, drawing parallels to OpenAI's o1 scaling plots. The article provides guidance on selecting a good default configuration by comparing performance versus cost, using data from the Artificial Analysis Coding Agent Index. It highlights trade-offs, such as Luna with Extra High effort potentially outperforming Sol with Medium effort at a lower cost, helping readers navigate the complex decision matrix.