Bundled skill validator fails because Codex Python lacks PyYAML

What version of the Codex App are you using (From “About Codex” dialog)?

26.519.41501

What subscription do you have?

Plus

What platform is your computer?

Windows 11

What issue are you seeing?

Codex bundled skill validator fails because bundled Python lacks PyYAML.

Environment:

• Codex desktop.
• Windows.
• Bundled Python: C:\Users\steph\.cache\codex-runtimes\codex-primary-runtime\dependencies\python\python.exe.
• Validator: C:\Users\steph\.codex\skills\.system\skill-creator\scripts\quick_validate.py.

Observed:
Running quick_validate.py with Codex’s bundled Python fails immediately:

ModuleNotFoundError: No module named 'yaml'

Expected:
A built-in Codex skill toolkit script should run with Codex’s bundled runtime, or avoid undeclared external dependencies.

Impact:
Codex cannot validate skills using its own documented skill-creator workflow unless the user supplies an unrelated local Python environment or installs PyYAML manually.

What steps can reproduce the bug?

1. Open Codex on Windows.

1. Use Codex’s bundled skill creator validator:

C:\Users\steph\.codex\skills\.system\skill-creator\scripts\quick_validate.py.

1. Run it with Codex’s bundled Python:

C:\Users\steph\.cache\codex-runtimes\codex-primary-runtime\dependencies\python\python.exe C:\Users\steph\.codex\skills\.system\skill-creator\scripts\quick_validate.py C:\Users\steph\.agents\skills\archive_doc

1. Observe that the script exits before validating the skill with:

ModuleNotFoundError: No module named 'yaml'

What is the expected behavior?

quick_validate.py should validate the skill folder using Codex’s bundled runtime, or the bundled runtime should include the script’s required dependencies.

Additional information

_No response_