Reasoning Mode

Reasoning mode is a model or API setting that changes how much internal work a model performs before returning a final answer. It is used with reasoning models and tasks that benefit from planning, checking, or multi-step problem solving.

Reasoning mode is related to, but different from, reasoning effort. Effort usually controls the amount of compute or tokens allocated to reasoning. Mode can change the execution behavior itself, such as enabling a quality-first path that performs more internal work before producing one final response.

Use reasoning mode when:

• the task is difficult enough to benefit from extra inference;
• a marginal quality gain is worth additional latency and cost;
• the output can be checked against clear criteria; and
• the application can tolerate less predictable response time.

Avoid it for routine classification, simple extraction, autocomplete, or high-volume workloads where low latency matters more than difficult reasoning. The right setting should be chosen through evaluation, not by assuming that more reasoning is always better.

OpenAI describes reasoning mode and reasoning effort as separate controls in its model guidance documentation.