shzx

Human-readable approval guard for AI coding agents.

shzx sits between an AI coding agent and your terminal. Every shell command is intercepted, translated into plain English, assigned a risk level, and shown to you for approval — before anything runs.

Stop blindly approving rm -rf commands. Know what your AI agent is doing.

Works with Claude Code, Codex, and Anti-Gravity.

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Why shzx?

AI coding agents are powerful — but they run shell commands on your machine. One wrong rm -rf, one curl | bash, and your work is gone. shzx gives you:

• Plain English summaries — no more guessing what find . -name "*.log" -exec rm {} \; does
• Risk scoring — every command rated low, medium, high, or critical
• Automatic blocking — critical-risk commands are denied before they can run
• File write protection — flags writes to .env, credentials, system paths, and shell scripts
• Zero config — one command to install, works immediately
• Colored output — risk levels are color-coded so you never miss a warning
• NO_COLOR support — respects the no-color.org standard

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Example

Agent proposes:

find /Users/oha/project -name "*.log" -exec rm {} \;

shzx shows:

[shzx] Risk: HIGH
[shzx] Summary: Search /Users/oha/project for files named *.log and delete them.
[shzx] Intent: Find and permanently delete files
[shzx] Warning: High Risk: This searches for files and permanently deletes them automatically.

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Quick Start

pip install .
shzx-install

That's it. Two commands. shzx is now guarding your terminal.

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Setup

Claude Code (hooks)

pip install .
shzx-install

shzx-install writes the hook config into ~/.claude/settings.json automatically. It registers hooks for Bash, Write, and Edit tools.

To uninstall:

shzx-uninstall

How it works with Claude Code:

• Critical risk — command is automatically blocked. Claude gets the analysis and must find a safer approach.
• High / Medium / Low risk — triggers an approval prompt showing the risk analysis. You decide.

shzx also intercepts Write and Edit tool calls, flagging sensitive files (.env, credentials, system paths) and shell scripts.

Codex

Codex hardcodes /bin/bash for command execution, so shzx can't intercept commands automatically. Instead, add instructions to your project's AGENTS.md:

## Shell Safety

Before running any shell command, evaluate it through shzx first:

\`\`\`bash
explaincmd "the command you want to run"
\`\`\`

If the risk is **high** or **critical**, explain the risks to the user and ask
for explicit approval before proceeding. Never run critical-risk commands without
confirmation.

This tells Codex to check commands through shzx before executing them. It won't block commands automatically like the Claude Code hook does — it relies on Codex following the instructions.

Anti-Gravity

shzx is integrated as a workflow. Ask Anti-Gravity to use the /explain_commands workflow or to evaluate commands through shzx.py.

Manual / Standalone

shzx -c "any command here"

Use --no-color or set the NO_COLOR environment variable to disable colored output.

For JSON output (useful for scripting and CI):

explaincmd "any command here"

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How It Works

shzx parses each command (including pipes, &&, ; chains, command substitutions, and bash -c wrappers) and evaluates:

• Effects — reads files, writes files, deletes files, network access, privilege escalation, git state changes
• Risk level — low (safe), medium (be aware), high (review carefully), critical (auto-blocked)
• Intent — what the command is trying to accomplish in plain English
• Warnings — specific dangers (force flags, in-place edits, remote code execution, recursive deletes, etc.)

Risk Levels

Level	Score	What happens
Low	0–19	Prompt shown with analysis
Medium	20–49	Prompt shown with analysis
High	50–89	Prompt shown with warnings
Critical	90+	Automatically blocked

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Supported Commands

File operations: find, rm, mv/cp, ln, chmod/chown, mkdir/touch, tee, sed, tar, zip/unzip

Viewing: ls/pwd/tree/wc/cat/less/more/head/tail, grep/rg, awk, jq

Network: curl/wget, ssh/scp, rsync, nc/ncat/netcat, telnet, nmap, tcpdump

Package managers: npm/yarn/pnpm/pip/cargo

Shell/scripting: bash/sh, python/node/ruby, xargs, echo

Git: git (status, log, diff, clean, reset, push, etc.)

System admin: sudo, kill/killall/pkill, systemctl/service, crontab, passwd, useradd/userdel/groupadd, mount/umount, dd, fdisk/mkfs/parted

Security/firewall: iptables/ufw/nft, openssl, gpg, base64

Containers: docker (run, exec, rm, build, pull, push)

Other: make, open/xdg-open, pbcopy/pbpaste/xclip

Unknown commands get a generic handler that still detects file path arguments and flags.

Inline Code Analysis

shzx scans inline code passed to python -c, node -e, and ruby -e for dangerous patterns like os.system(), child_process, eval(), file deletion, and network access. The code snippet is included in the summary so you can see exactly what's being executed.

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Project Structure

shzx.py    — CLI entrypoint. Arg handling, colored display, user confirmation.
analyzer.py     — Tokenizes commands, computes risk level, checks dangerous compositions.
handlers.py     — Command handlers. Knows what 30+ commands do.
constants.py    — Named risk score constants and thresholds.
hook.py         — Claude Code PreToolUse hook (Bash, Write, Edit). Colored output.
install.py      — Installs/uninstalls hooks into ~/.claude/settings.json.
explaincmd.py   — Standalone JSON output mode.
tests/          — 242 tests (unit + integration).

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Contributing

See CONTRIBUTING.md for guidelines. All contributions welcome — new command handlers, better risk heuristics, integrations with other agents.

Changelog

See CHANGELOG.md for release history.

License

Apache License 2.0 — see LICENSE.