DCG: Pre-Execution Safety

DCG (Destructive Command Guard) is a Claude Code hook that blocks dangerous commands before they execute. It protects your repos from hard resets, recursive deletes, destructive database commands, and more.

Think of it as a safety interlock: if a command looks destructive, DCG stops it and suggests a safer alternative.

DCG runs as a PreToolUse hook inside Claude Code. Every command is checked against a set of rules before it runs.

# Example: test a command before running it
$ dcg test "git reset --hard" --explain
> BLOCKED: git.reset.hard
> Why: hard reset discards uncommitted work
> Safer: git restore --staged .

If you need to remove DCG, you can uninstall the hook and optionally purge the binary and config. You can always re-enable it later with dcg install.

# Remove hook only (keeps dcg installed)
$ dcg uninstall
# Full removal (hook + binary + config)
$ dcg uninstall --purge
# Verify removal
$ dcg doctor
$ claude /hooks

Packs let you enable or disable rules based on your workflow. Keep the ones you need to avoid false positives.

# ~/.config/dcg/config.toml
[packs]
enabled = ["git", "filesystem", "database.postgresql", "containers.docker"]

A block is a warning, not a dead end. Use it as a checkpoint:

• Read the explanation carefully.
• Prefer the safer alternative when possible.
• Use allow-once only if you are confident.
• Document the decision in your commit or notes.