code-reuse-guard

code-reuse-guard is a cursor rule for Cursor from TashanGKD/tashan-cursor-skills. It costs 1,589 tokens per session, scanned A, original, MIT.

A rule for reusing existing code when the user explicitly asks for reuse or copying. It requires the agent to find and verify the original implementation before calling or copying it.

In plain words
What is it for?
Use it when adapting an existing function, component, interface, or module to a new place. It helps locate the source, confirm its functions exist, and reuse the implementation directly.
Why use it?
It prevents the agent from quietly writing a new version instead of reusing the requested code. If the existing code cannot be reused, it stops and reports the obstacle.

Cursor rule for Cursor

Written for Cursor: a Cursor rule (.mdc). Also seen: built for openclaw.

Good fit Use it when adapting an existing function, component, interface, or module to a new place. It helps locate the source, confirm its functions exist, and reuse the implementation directly.

Compare 6 cursor rules from other repositories ↓
Install with agentmods
npx agentmods add rules/tashangkd/tashan-cursor-skills/code-reuse-guard
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/TashanGKD/tashan-cursor-skills

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 code-reuse-guard

README.md
[![agentmods](https://agentmods.dev/badge/rules/tashangkd/tashan-cursor-skills/code-reuse-guard.svg)](https://agentmods.dev/rules/tashangkd/tashan-cursor-skills/code-reuse-guard)
Your own site
<a href="https://agentmods.dev/rules/tashangkd/tashan-cursor-skills/code-reuse-guard"><img src="https://agentmods.dev/badge/rules/tashangkd/tashan-cursor-skills/code-reuse-guard.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,589 This file is loaded in full into every session.
When invoked 1,589 The same file — it is already loaded in full.
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 $0.01589 $0.01589
Opus 5 $0.00794 $0.00794
Sonnet 5 $0.00318 $0.00318
Haiku 4.5 $0.00159 $0.00159

Measured 7d ago against content hash 31535367fc61, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

code-reuse-guard 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 7d 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.

rules/code-reuse-guard.mdc · 118 lines

How it starts

The opening of the file, as written. The whole thing — 118 lines — stays where its author put it; the contents beside it link to each section on GitHub.

复用指令执行守护规则(code-reuse-guard)

核心问题:当用户说「复用X」时,AI 本能会做「理解X的原理,然后重新实现相同行为」。 这是训练出来的「生成最优解」本能——但在用户明确指定执行路径时,这个本能是有害的。

用户说「复用」= 找到那段能跑的代码,在新地方也用它 不是「理解X的工作原理,用相同原理写一个新版本」


触发条件

用户消息中出现以下任意关键词,且任务属于开发/实现类(代码、架构、接口、组件):

  • 复用完全复用全量复用
  • 直接复制copy过来抄过来
  • 不要重新写不要重新实现
  • 跟X一样(X是已有的代码模块/函数/接口)

激活后强制执行的序列(不可跳过)

Step 1 【定位原始实现】
 使用 grep/glob 在代码库中找到用户所说「X」的实际文件路径和函数/接口名称
 → 不允许基于印象或推断写调用代码
 → 必须实际读取原始文件,确认实现存在

Step 2 【确认存在性】
 检查所有将被调用的函数/类/接口是否真实存在于代码库中
 → 若发现不存在 → 立即停止,告知用户「X中的Y函数不存在,无法直接复用」
 → 不允许假设函数存在后继续写调用代码

Step 3 【复制或直接调用】
 将原始实现的代码路径直接复制/调用到新场景
 → 允许:修改参数名/变量名以适配新场景
 → 允许:导入新的依赖(若原始实现依赖某个模块)
 → 不允许:理解原理后「重新实现一个更精巧的版本」
 → 不允许:以「这部分逻辑不完全适用」为由跳过原始代码,写新的替代实现

Step 4 【遇障碍停止汇报,不自主换方案】
 若发现原始实现的某部分无法直接复用(如依赖不兼容/接口签名不匹配):
 → 停止,向用户汇报:「复用X遇到了障碍:[具体障碍]」
 → 提供选项:(a) 接受障碍并调整 (b) 换方案 (c) 跳过该部分
 → 等待用户决策,不自行切换到「重新设计」模式

「完全/全量」硬性信号

当用户使用「完全」「全量」「注意是完全」等强调词时,这是硬性约束

❌ 绝对禁止:以「这部分逻辑不适用当前场景」为由精简或省略原始代码的任何部分
❌ 绝对禁止:把「不能全部复用」变成「重新设计整体架构」
✅ 正确行为:复制所有相关代码 → 若遇到无法复用的部分 → 停止并列出具体障碍 → 等用户指令

禁止行为(硬性清单)

❌ 禁止:在没有 grep 确认的情况下写任何调用代码
❌ 禁止:遇到「部分依赖复杂」就静默切换到重新实现
❌ 禁止:「我理解了X是怎么工作的,让我实现一个等效版本」
❌ 禁止:调用一个自己假设存在但未验证的函数
❌ 禁止:发现技术障碍后自主更换整体方案,而不先汇报给用户
❌ 禁止:把「复用参考」当作「复用代码」——参考架构后重写 ≠ 复用

「复用」与「参考」的区别

场景 用户意图 正确行为
「复用老版本的proxy模式」 直接使用已有的proxy代码路径 grep找到proxy相关函数,调用同一条调用链
「把openclaw复制过来」 字面意思复制代码文件 cp -r 或逐文件复制,不是重新设计
「参考openclaw的设计」 理解设计思路,新写 可以重新实现(这不是「复用」指令)
「跟proxy一样,只是换个参数」 改一个参数,其余不变 找到proxy实现,只改那一个参数,其余照抄

与现有规则的关系

规则 关系
session-bootstrap.mdc A1.7 本规则被 A1.7 引用,在触发词检测阶段激活
knowledge-integrity-rules.mdc R3 READ_FIRST 复用前必须先读原始文件(R3 兼容)
role-后端开发 / role-前端开发 extends:开发角色收到复用指令时,本规则提供额外约束

变更记录

2026-03-22 — v1.0 — 初始创建

根因:2026-03-22 对话历史分析(1dc992d0/9d4ef11b/a4a4b82a)发现系统性模式:用户说「复用X」时,AI 将其解读为「理解X原理→重新实现」,而非「找到X代码→直接用」。最典型:用户说「完全复用老版本proxy模式」,AI写了新代码并调用了不存在的函数,导致FOLLOWUPS完全失效。跨3个对话出现5次同类偏差。

Read the full file on GitHub · 118 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. 7d ago First seen · 118 lines · 1,589 tokens per session scan A 31535367fc61

Subscribe to this mod's changes

code-reuse-guard is a cursor rule published in the GitHub repository TashanGKD/tashan-cursor-skills (20 stars, last pushed 5mo ago), licensed MIT. It adds 1,589 tokens to every session, about $0.0079 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.