codex - 💡(How to fix) Fix [BUG] Can't switch reasoning effort to Xhigh in Codex app [2 comments, 2 participants]

TL;DR

The issue may be resolved by checking the compatibility of the Codex app version with the GPT-5.4 model and the Xhigh reasoning effort setting.

Guidance

• Verify that the Codex app version 26.406.31014 supports the Xhigh reasoning effort setting for the GPT-5.4 model.
• Check if there are any known issues or limitations with the Xhigh setting in the Codex app documentation or release notes.
• Try resetting the Codex app settings to their default values to see if the issue persists.
• If possible, test the Xhigh setting with a different model to isolate the issue.

Example

No code snippet is provided as it is not explicitly supported by the issue.

Notes

The issue may be specific to the combination of the Codex app version, GPT-5.4 model, and Xhigh reasoning effort setting. Further investigation is needed to determine the root cause.

Recommendation

Apply workaround: Try using a different model or resetting the app settings to see if the issue persists, as the current combination may not be compatible.