Claude Code
Open/model. Effort is shown under the model list, for example High effort. Use the left and right arrow keys to change it. Enter saves it as the default. s applies it to this session only.
Codex and the ChatGPT desktop app
Open the model picker. In the Codex CLI that is/model, titled Select Model and Effort. Choose the effort there. The ChatGPT desktop app reads the same Codex config, so the effort applies to both.
Other harnesses
Use the harness’s own effort control where it has one. Nexus CLI does not set effort for you.Related
- Nexus Auto: how
autopicks a model for each turn - Claude Code
- Codex