rein-cleanup

rein-cleanup is a cursor rule for Cursor from jstxn/rein. It costs 13 tokens per session (800 once invoked), scanned A, original, MIT.

A cleanup and refactoring workflow for reducing noisy, repetitive, dead, or unnecessarily complicated code while preserving its behavior. It starts with regression tests and keeps changes within the requested scope.

In plain words
What is it for?
Use it when working code needs cleanup, refactoring, or removal of duplicate and dead code. It is also for improving tests and boundaries without rewriting unrelated areas.
Why use it?
It lowers the risk that a cleanup will accidentally change how the software works. Tests and a bounded plan provide evidence before and after the edits.

Cursor rule for Cursor

Written for Cursor: installed under .cursor/.

Good fit Use it when working code needs cleanup, refactoring, or removal of duplicate and dead code. It is also for improving tests and boundaries without rewriting unrelated areas.

Compare 6 cursor rules from other repositories ↓
Install with agentmods
npx agentmods add rules/jstxn/rein/rein-cleanup
View source ↗ jstxn/rein
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Clone the repo
git clone --depth 1 https://github.com/jstxn/rein

Made for: Cursor.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for rein-cleanup

README.md
[![agentmods](https://agentmods.dev/badge/rules/jstxn/rein/rein-cleanup.svg)](https://agentmods.dev/rules/jstxn/rein/rein-cleanup)
Your own site
<a href="https://agentmods.dev/rules/jstxn/rein/rein-cleanup"><img src="https://agentmods.dev/badge/rules/jstxn/rein/rein-cleanup.svg" alt="Measured on agentmods" height="20"></a>
Per session 13 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 800 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00013 $0.00800
Opus 5 $0.00006 $0.00400
Sonnet 5 $0.00003 $0.00160
Haiku 4.5 $0.00001 $0.00080

Measured 8d ago against content hash ab66bc9404ce, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

rein-cleanup scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 8d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.cursor/rules/rein-cleanup.mdc · 93 lines

How it starts

The opening of the file, as written. The whole thing — 93 lines — stays where its author put it; the contents beside it link to each section on GitHub.

rein-cleanup

Reduce bloated, noisy, repetitive, or over-abstracted code with a regression-tests-first, smell-by-smell cleanup workflow that preserves behavior and raises signal quality.

When to Use

Use this skill when:

  • A code path works but feels bloated, noisy, repetitive, or over-abstracted
  • A user asks to "cleanup", "refactor", or "deslop" output
  • Follow-up implementation left duplicate code, dead code, weak boundaries, missing tests, or unnecessary wrapper layers
  • You need a disciplined cleanup workflow without broad rewrites

Scoped File Lists

  • This skill can accept a file list scope instead of a whole feature area.
  • When the caller provides a changed-files list, keep the cleanup strictly bounded to those files.

Procedure

  1. Lock behavior with regression tests first

    • Identify the behavior that must not change
    • Add or run targeted regression tests before editing cleanup candidates
    • If behavior is currently untested, create the narrowest test coverage needed first
  2. Create a cleanup plan before code

    • List the specific smells to remove
    • Bound the pass to the requested files or scope
    • If a file list scope is provided, keep the pass restricted to that changed-files list
    • Order fixes from safest and highest-signal to riskiest
    • Do not start coding until the cleanup plan is explicit
  3. Categorize issues before editing

    • Duplication: repeated logic, copy-paste branches, redundant helpers
    • Dead code: unused code, unreachable branches, stale flags, debug leftovers
    • Needless abstraction: pass-through wrappers, speculative indirection, single-use helper layers
    • Boundary violations: hidden coupling, leaky responsibilities, wrong-layer imports or side effects
    • Missing tests: behavior not locked, weak regression coverage, gaps around edge cases
  4. Execute passes one smell at a time

    • Pass 1: dead code deletion
    • Pass 2: duplicate removal
    • Pass 3: naming and error handling cleanup
    • Pass 4: test reinforcement
    • Re-run targeted verification after each pass
    • Avoid bundling unrelated refactors into the same edit set

Read the full file on GitHub · 93 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 8d ago First seen · 93 lines · 13 tokens per session scan A ab66bc9404ce

Subscribe to this mod's changes

rein-cleanup is a cursor rule published in the GitHub repository jstxn/rein (12 stars, last pushed 4mo ago), licensed MIT. It adds 13 tokens to every session and 800 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.