Per project custom PROMPTS are broken

What version of Codex is running?

0.63.0

What subscription do you have?

PRO

Which model were you using?

gpt-5.1

What platform is your computer?

Darwin 24.6.0 arm64 arm

What issue are you seeing?

When creating a .codex/prompts directory inside the project to add custom-discover.md command per project, the codex wouldn't pick any of the commands, regardless of what I try.

What steps can reproduce the bug?

Uploaded thread: 019ac99b-6723-7de2-899b-d2b09ccb0a85

1. Create a new directory ./custom-project
2. Change to that directory
3. Make a directory called .codex/prompts/
4. Create a new custom command in the .codex/prompts and name it discover.md
5. Assign some execution plan for the project, such as "Describe the deployment process for this project."
6. Launch codex and try to run /discover
7. Observe that it's not even in a list, also this error shows up Unrecognized command '/discover'. Type "/" for a list of supported commands.

What is the expected behavior?

The expected behavior is for it to show up in the list of slash commands when typing slash and then be able to start the execution of what written in discover.md, so it should explain me the details of deployment process.

Additional information

The custom prompts are important to be preserved per project basis, since it makes context initialization per project possible. It also lets you to commit prompts with git and share them with team members. Claude also has this functionality and people find it helpful.