Prerequisites
Code Guardian runs as a skill and hook package inside Claude Code, and for the Codex output also inside the OpenAI Codex CLI. This page lists what must be present before the installer runs.
Required tools
| Tool | Requirement |
|---|---|
| Claude Code | baseline requirement |
| OpenAI Codex CLI | only for the Codex output |
| Python | version 3.9 or newer, standard library only, no additional packages |
| Bash and git | both required |
| jq | if missing, the installer runs anyway and then exits with code 3. Without jq, only the four command guards in the Claude edition (deletion, deployment, migration, commit secrets) keep checking, because they run in Python; without jq, the write guard for unattended runs and the autopilot stop for option questions block nothing. In the Codex edition, the dispatcher stops every command without jq. |
| shasum or sha256sum | for checksums, either one is enough |
Recommended, not required: the obra/superpowers package.
Platforms
- macOS
- Linux
- Windows, natively via Git Bash (Git for Windows)
- Windows, fully inside WSL 2
The mixed form is not supported: Claude Code running on Windows while the checks run through WSL.
Windows
C:\Windows\System32\bash.exeis the WSL launcher, not Git Bash. Code Guardian deliberately never calls it.- Inside WSL, keep the project in the Linux filesystem, under
~/, not under/mnt/c. The guard scripts read files on every command, and/mnt/ccosts noticeably more time. - Install Python via
winget install Python.Python.3.12or the python.org installer, not the Microsoft Store stub. The stub passes every existence check but cannot actually run. The result: every guard script asks before every command. - Install jq on Windows via
winget install jqlang.jq. - If Python is still missing, the guard scripts do not stay silent: they ask before every command, and a line is written to
~/.claude/code-guardian-failopen.log. - Checking takes noticeably longer on Windows than on macOS or Linux, because every program start costs more there. Measured on GitHub
windows-latest: a median of about 1700 ms before a Bash command and 600 ms after it, and the median total per call is about 2400 ms. - At session start on Windows, Code Guardian measures what a program start costs on your machine and warns you if the guards' time limit is too tight for it.
- The tool detection recognises the Microsoft Store
python3placeholder for what it is and does not count it as an installed Python.
In one sentence
Python 3.9 or newer, Bash, git and jq are all it needs; on Windows add Git Bash or a complete WSL 2, never a mix of both.