Reasoning efforts on GPT-5.6 Sol: Start with the lowest setting that gets the job done, then turn it up only when the task actually needs more thinking. > Light & Low: quick, well-scoped tasks > Medium: planning, analysis, or a few moving parts > High & xhigh: harder work with multiple steps, tradeoffs, research, or careful verification Max and Ultra are a bit different: > Max: one model spends longer working through one hard problem > Ultra: multiple subagents work on different parts of a bigger problem in parallel Oh and, as with any new model, the reasoning levels don’t map directly from GPT-5.5 to GPT-5.6. If you’re used to 5.5, try starting one level lower on a familiar task, then increase it only if the result needs it.