This is how development looks like for many years now, constant rewrite on the horizon. I think LLM development hype surpassed Blockchain and JS frameworks craze of decade ago.
CLAUDE.md (or AGENTS.md) is not good place to put all code change rules, because these rules would dillute the context and "distract" the agent e.g. during bugs triage or business analysis.
Instead modularize the knowledge with skills and specialized MD files. Agent should lazy load what is needed to do focused work.
Skills have usage description metadata, but with free files you can simply instruct agent with CLAUDE.md to load them, e.g.: "Before you attempt to change any frontend code first load and follow `docs/{JS|HTML|CSS}_coding_rules.md`".
The worst is that every agent session is generating so many "btw fix this" side-quests that it is really hard to stay in the task focus. I throw some into todo list manually but still it is exploding by the day. Perfect is enemy of good.
In my place I see currently a governance panel effort mandating around LLM agent skills usage, it is so much shit show that I expect productivity is going to fall to 0.5x pre-agents. But not pre-LLM as autocompletion was really helpful in the trenches. The tool in wrong governing hands and you get sand into cogs thrown.
... and that actually shows - senior engineers have spent actual paid time to train juniors. Plus they used to spent time contributing to open source projects or Stack Overflow, all the stuff which every company benefits from.
You need to create review skill and there define what "issue" or "good" are for you to limit sensitiviness. Otherwise you depend on model's random threshold or non of such then you get perfection chasing.
Anyway it will never match your judgemend completely unless you upload your brain dump into model.
I still amazed how so many people don't get this entire planet is one feedback loop system of competing life processes and they think hiding in their dusty houses with artificial cures will keep them away from competition and immune against death.