python3 not found on Windows (Git Bash) — codex skills fail on first run

[alazc]

Bug

The /codex skill hardcodes python3 in its Bash pipe commands for parsing codex JSON output. On Windows (Git Bash / MSYS2), Python installs as python, not python3, causing:

/usr/bin/bash: line 238: python3: command not found

The skill fails on first invocation, then sometimes works on retry (likely due to shell environment initialization quirks).

Affected files

• codex/SKILL.md.tmpl — 3 instances (lines ~290, ~434, ~476)

All are the same pattern:

... | PYTHONUNBUFFERED=1 python3 -u -c "

Suggested fix

Replace bare python3 with a cross-platform probe:

PYTHON_CMD=$(command -v python3 2>/dev/null || command -v python 2>/dev/null || echo python)
... | PYTHONUNBUFFERED=1 $PYTHON_CMD -u -c "

This tries python3 first (Linux/macOS), falls back to python (Windows), and fails clearly if neither exists.

Environment

• Windows 11, Git Bash (MSYS2)
• Python 3.11.6 installed as python (standard Windows installer)
• gstack v1.26.0.0

[jbetala7]

Opened PR #1316 to fix this: #1316

It resolves python3 first and falls back to python before the Codex JSONL parser runs, so Windows Git Bash installs that expose Python as python do not fail on the hardcoded python3 pipe. The PR also fails clearly if neither interpreter is present and adds a regression test for the generated command shape.