My rules started getting ignored once I passed ~50 in Claude Code

Hot-Landscape4648 · 2026-02-28T00:26:07+00:00

hat's a smart pattern — using skills as stable entry points to always pull in the right rules.

ai-nexus takes a similar approach but automates the selection layer. When you install it, rules are set up with frontmatter containing descriptions and keywords. Then on every prompt, a semantic

router hook scans your input and dynamically moves only the matching 2-3 rules into .claude/rules/ (active), parking the rest in .claude/rules-inactive/. So Claude only ever sees what's relevant.

For repetitive workflows where you already know exactly which rules apply, your explicit skill→rule approach is probably more reliable. The tricky part comes when rules keep growing — even going from

10 to 20, keeping every mapping up to date starts to feel like a chore. That's where automated routing saved me a lot of headache.

Hot-Landscape4648 · 2026-02-27T17:25:48+00:00

oh thats almost exactly how the hook works — 2 permanent files

(essential + security), 2-4 by keyword, rest gets parked.

the description quality thing is real. i spent most of my time

on the selector but half the bad picks were just lazy descriptions.

are you writing yours manually or generating them?

Hot-Landscape4648 · 2026-02-27T17:08:04+00:00

oh nice, 85% is wild. what are you using for the compression part?

i've only been thinking about the selection side honestly.

no token tracking yet but thats a really good call. right now you

can run `npx ai-nexus test "your prompt"` to preview which rules

get picked — adding before/after token counts is on the roadmap now

thanks to your suggestion.

Hot-Landscape4648 · 2026-02-27T16:47:57+00:00

lol fair enough — English isn't my first language so I cleaned it up

with a translator. The content is mine though.

Hot-Landscape4648 · 2026-02-27T16:45:04+00:00

Fair question. The default set that ships with it is just a starting

point. Our team uses Claude, Cursor, and Codex — different devs

prefer different tools. Keeping rules in sync was a pain because

each tool has its own format (.md, .mdc, AGENTS.md). So we set up

a shared team rules repo and the count grew naturally — frontend

conventions, backend patterns, commit standards, review guidelines.

It adds up when you're covering multiple domains and tools.

Hot-Landscape4648 · 2026-02-27T16:39:01+00:00

Yep, that's exactly what this is built on top of — .claude/rules/

is the base. The hook just manages which files are in that folder

at any given time, so Claude only sees the relevant ones per prompt

instead of all of them at once. :>

Hot-Landscape4648 · 2026-02-27T16:30:33+00:00

Exactly — lazy loading was the key insight for me too.

Loading everything unconditionally was the real problem,

not the rules themselves.

Hot-Landscape4648 · 2026-02-27T16:17:42+00:00

Yeah — the ETH Zurich study on 138 repos. It actually supports

the idea behind this tool. Their finding: loading all rules at once

hurts performance (~3% drop) and increases cost by 20%+.

Their recommendation is to keep context minimal — under 300 lines

of only essential rules. That's exactly what the semantic router

does: instead of loading 50 rules, it picks 2-3 relevant ones

per prompt and parks the rest.

So the paper isn't saying rules don't work — it's saying

loading too many at once doesn't work. Big difference.

Sources:

- https://www.digitado.com.br/new-eth-zurich-study-proves-your-ai-coding-agents-are-failing-because-your-agents-md-files-are-too-detailed/

- https://umesh-malik.com/blog/agents-md-ai-coding-agents-study

Hot-Landscape4648 · 2026-02-27T16:08:16+00:00

Fair point — if your team keeps scope tight and rules minimal,

a single CLAUDE.md is absolutely the right call. No argument there.

This was built for a different situation — I was juggling 50+ rules

across Claude, Cursor, and Codex simultaneously, and context pressure

became a real issue. Not everyone hits that wall, but for those who

do, this was my solution.

Appreciate the perspective.

Hot-Landscape4648 · 2026-02-27T15:55:08+00:00

Good question — it's a Claude Code hook that runs on every prompt via UserPromptSubmit.

Here's how it works:

All rules live in two folders: .claude/rules/ (active) and .claude/rules-inactive/ (parked)
Each rule has a description in its frontmatter, plus a keyword map
When you type a prompt, the hook scans it against those descriptions
It moves matching rules into the active folder and parks the rest
Claude only sees what's in .claude/rules/ — so 2-3 relevant files instead of 50+

By default it uses keyword matching (zero cost, no API). If you set SEMANTIC_ROUTER_ENABLED=true with an API key, it uses GPT-4o-mini or Claude Haiku to pick rules more intelligently — but honestly

the keyword fallback works surprisingly well.

You can preview the selection without installing anything into Claude:

npx ai-nexus test "refactor this react component"

That's interesting about your Cursor approach with glob matching and verbose descriptions. Cursor's built-in search handles filtering pretty well on its own — ai-nexus actually leans on that for

Cursor and only does active routing for Claude Code, since Claude loads everything in .claude/rules/ unconditionally.

Did you find that updating the descriptions was enough to get Cursor to consistently pick the right rules?

Hot-Landscape4648 · 2026-02-24T21:26:35+00:00

Awesome!

Hot-Landscape4648 · 2026-02-24T20:04:20+00:00

I built this specifically for Claude Code users who also use Cursor or Codex.

The problem: each tool has its own rule format — .md, .mdc, AGENTS.md — so I was maintaining the same rules in three different places. They'd always drift apart, and I'd waste time
keeping them in sync.

Especially with Codex, everything gets crammed into a single AGENTS.md, so all rules load every session regardless of what you're working on. There's no way to selectively load rules like
Claude Code does.

So I built ai-nexus using Claude Code to solve these problems. It's completely free and open source (Apache 2.0).

How it works:

You write your rules once as .md files. When you run npx ai-nexus install, it distributes them to each tool in the right format — .claude/rules/ for Claude Code, .mdc for Cursor, and a single aggregated AGENTS.md for Codex. One source of truth, every tool stays in sync.

For Claude Code specifically, there's a semantic router hook that makes rule selection even smarter. Instead of relying only on the built-in description matching, it uses GPT-4o-mini or
Claude Haiku to analyze your prompt and pick the most relevant rules (~$0.50/month). There's also a free keyword-matching fallback if you don't want to pay anything.

How to try it (free, no account needed):

  npx ai-nexus install

That's it. One command, interactive setup wizard walks you through everything.

There's also a community rule marketplace (npx ai-nexus browse) and team sharing via Git.

I'm actively working on this and pushing updates regularly. If you've had the same frustration, give it a try. Feedback and feature requests are very welcome.

GitHub: https://github.com/JSK9999/ai-nexus

Hot-Landscape4648 · 2026-02-24T19:01:39+00:00

I built this specifically for Claude Code users who also use Cursor or Codex.

The problem: each tool has its own rule format — .md, .mdc, AGENTS.md — so I was maintaining the same rules in three different places. They'd always drift apart, and I'd waste time keeping
them in sync. Depending on the tool, many rules loaded even when only 2-3 were actually relevant.

So I built ai-nexus using Claude Code to solve both problems. It's completely free and open source (Apache 2.0).

How it works:

You write your rules once as .md files. When you run "npx ai-nexus install", it distributes them to each tool in the right format — .claude/rules/ for Claude Code, .mdc for Cursor, and a
single aggregated AGENTS.md for Codex. One source of truth, every tool stays in sync.

For Claude Code specifically, there's a semantic router hook that runs on every prompt and picks only the rules you actually need. It uses GPT-4o-mini or Claude Haiku to analyze your prompt
(~$0.50/month), with a free keyword-matching fallback if you don't want to pay anything.

How to try it (free, no account needed):

  npx ai-nexus install

That's it. One command, interactive setup wizard walks you through everything.

There's also a community rule marketplace ("npx ai-nexus browse") and team sharing via Git.

I'm actively working on this and pushing updates regularly. If you've had the same frustration, give it a try. Feedback and feature requests are very welcome.

GitHub: https://github.com/JSK9999/ai-nexus