We’ve been building visual rule engines (clear spreadsheet interfaces -> API endpoints that map incoming data to a large number of potential outcomes), and had the fun idea lately to see what happens when we use our decision table UI with Claude’s PreToolUse hook.

The result is a surprisingly useful policy/gating layer– these tables let your team:

- Write conditional, exception-friendly policies beyond globs/prefixes (e.g. allow rm -rf only in */node_modules/*, deny //$HOME, ask if --force or network call; gate kubectl delete / SQL DROP with a clear reason)

- Roll out policy changes instantly (mid-run, flip a risky operation from allow → ask; the next attempt across devs and agents is gated immediately– no git pull or agent restart required)

- Adopt lightweight governance that is somewhat agent agnostic and survives churn (MCP/skills/etc)- just add columns/rules as new tools and metadata show up

- Gain a central utility to understand which tools are being used, which tools get blocked most often, and why