Found a bug in Codex.
Nobody has claimed this yet.
- Dominant language
- Rust
- Stars
- 125k
- Forks
- 19.4k
- PR merge metrics
- PR metrics pending
Description
Bug: Unable to select GPT-5.4 mini
Hello!
I found a small bug: it is currently impossible to select the GPT-5.4 mini model.
Regardless of which reasoning effort level is selected, whenever I try to switch from GPT-5.4 to GPT-5.4 mini, it automatically switches back to GPT-5.6 Luna (Medium).
I would appreciate it if you could look into this and fix the issue.
Also, I’d be happy to receive any kind of reward for reporting this small bug or finding this issue. 🙂
Thank you!
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by reproducing the model switch in the Codex terminal interface, using different reasoning-effort levels while changing from GPT-5.4 to GPT-5.4 mini. Trace the model-selection entry point and verify that GPT-5.4 mini remains selected rather than switching to GPT-5.6 Luna (Medium).
Written by the indexing model from the issue text.
Assessment
- Tech stack
- rust
- Domain
- ai, cli
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Active
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100