I've been coming at this from a slightly different angle, building a system that encodes checks that run against code authored by Claude, with escalating levels of enforcement.
It's still really early, but, among early users, we see that about 40% of agent turns produce code that violates the guidance in the project's own CLAUDE.md. We catch the violations at the end of the turn and direct Claude to correct them.
Still looking for early users and feedback. http://getcaliper.dev