Tandem vendoring note. Vendored from gstack (MIT, (c) Garry Tan, https://github.com/garrytan/gstack @ a3259400). The upstream Claude-Code-specific boilerplate (telemetry, session tracking, update checks, plan-mode hooks, learnings/brain sync) was removed; the workflow itself is unchanged. Paths below are relative to this skill's directory; sibling skills live at ../<id>/ (ids are prefixed gstack-). $GSTACK_ROOT is an optional upstream gstack install (default ~/.claude/skills/gstack) needed only for optional helpers such as the browse binary; skip any step that needs it when it is absent. "Ask the user" means a plain chat question when no structured question tool exists.

When to invoke this skill

Combines /careful (warns before rm -rf, DROP TABLE, force-push, etc.) with /freeze (blocks edits outside a specified directory). Use for maximum safety when touching prod or debugging live systems. Use when asked to "guard mode", "full safety", "lock it down", or "maximum safety".

/guard — Full Safety Mode

Activates both destructive command warnings and directory-scoped edit restrictions. This is the combination of /careful + /freeze in a single command.

Dependency note: This skill references hook scripts from the sibling /careful and /freeze skill directories. Both must be installed (they are installed together by the gstack setup script).

Setup

Ask the user which directory to restrict edits to. Use ask-the-user:

• Question: "Guard mode: which directory should edits be restricted to? Destructive command warnings are always on. Files outside the chosen path will be blocked from editing."
• Text input (not multiple choice) — the user types a path.

Once the user provides a directory path:

1. Resolve it to an absolute path:

FREEZE_DIR=$(cd "<user-provided-path>" 2>/dev/null && pwd)
echo "$FREEZE_DIR"

2. Ensure trailing slash and save to the freeze state file:

FREEZE_DIR="${FREEZE_DIR%/}/"
eval "$($GSTACK_ROOT/bin/gstack-paths)"
STATE_DIR="$GSTACK_STATE_ROOT"
mkdir -p "$STATE_DIR"
echo "$FREEZE_DIR" > "$STATE_DIR/freeze-dir.txt"
echo "Freeze boundary set: $FREEZE_DIR"

Tell the user:

• "Guard mode active. Two protections are now running:"
• "1. Destructive command warnings — rm -rf, DROP TABLE, force-push, etc. will warn before executing (you can override)"
• "2. Edit boundary — file edits restricted to <path>/. Edits outside this directory are blocked."
• "To remove the edit boundary, run /unfreeze. To deactivate everything, end the session."

What's protected

See /careful for the full list of destructive command patterns and safe exceptions. See /freeze for how edit boundary enforcement works.

Enforcement outside Claude Code (Tandem note)

Upstream enforces this skill with a Claude Code PreToolUse hook. Other agents have no such hook, so you must self-enforce: before every shell command or file edit, run the matching check script from this skill's bin/ directory (bin/check-careful.sh / bin/check-freeze.sh; they read the tool-input JSON on stdin) or apply the same rules by hand, and stop to ask the user whenever a rule trips. Tandem's own sandbox and permission cards remain the hard boundary.