How do I install the Code Reuse skill?

Run npx skillmds@latest add alex-macra/code-reuse in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Code Reuse safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Code Reuse?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Code Reuse free to use?

Yes. Installing skills from SkillMD is free. This skill is licensed under MIT.

Who published Code Reuse?

alex-macra (@alex-macra) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Code Reuse by alex-macra — Agent Skill

Name: Code Reuse
Author: alex-macra

Code Reuse

Reuse before writing: find the existing function, util, hook, or component and extend it instead of adding a near-duplicate. Use when adding a helper or utility, consolidating duplicate or copy-paste code, or reviewing a diff for reuse.

alex-macra df9d7de 2.3 KB Updated Sep 17, 2026

File contents

Code reuse

Before writing a function, hook, component, or script, assume it already exists somewhere in the repo. Go find it.

Search before you write

Grep for the concept, not the name you were about to give it - the existing function probably isn't called what you'd call it.
Check the project's existing dependencies before hand-rolling something a library already does.
When you report the change, name the search you actually ran. "Grepped for debounce, throttle; found none" is a claim someone can check. "Nothing else did this" is not.

Extend, do not fork

A near-duplicate function with one different line is a sign the original needs a parameter, not a sibling.
Exception: a boolean flag that switches between two behaviors is two functions wearing one name. Splitting them is not the duplication this skill is about - see architect-review's flag-parameter rule.

Rule of three, both directions

Don't abstract at two instances - a two-case abstraction usually fits neither case well.
Don't tolerate a third copy - by copy three, the shared shape is real. This is architect-review's rule; this skill exists to catch the moment before copy two.

What is not reuse

A wrapper around one call site that will only ever have one call site.
A re-export with no added behavior.
Reaching into a utils.ts grab-bag because it's there, when nothing in it is related to the problem.
Pulling in a new dependency to save five lines you could write directly.

Finish the move

Delete the code the reuse replaced. Two implementations of the same job outlive their reason to exist far longer than anyone plans for.

Reviewing for reuse

For every new function, file, or component in a diff, ask what already did this job. Answer with a symbol and a file path, or state plainly that you looked and found nothing.

What this skill is not

Not DRY absolutism. Two call sites that happen to share five lines by coincidence, not by concept, are not duplication - forcing them to share a helper couples things that should be free to diverge.

---name: code-reusedescription: Reuse before writing: find the existing function, util, hook, or component and extend it instead of adding a near-duplicate. Use when adding a helper or utility, consolidating duplicate or copy-paste code, or reviewing a diff for reuse.license: MIT---# Code reuseBefore writing a function, hook, component, or script, assume it already exists somewhere in the repo. Go find it.## Search before you write- Grep for the *concept*, not the name you were about to give it - the existing function probably isn't called what you'd call it.- Check the project's existing dependencies before hand-rolling something a library already does.- When you report the change, name the search you actually ran. "Grepped for `debounce`, `throttle`; found none" is a claim someone can check. "Nothing else did this" is not.## Extend, do not fork- A near-duplicate function with one different line is a sign the original needs a parameter, not a sibling.- Exception: a boolean flag that switches between two behaviors is two functions wearing one name. Splitting them is not the duplication this skill is about - see `architect-review`'s flag-parameter rule.## Rule of three, both directions- Don't abstract at two instances - a two-case abstraction usually fits neither case well.- Don't tolerate a third copy - by copy three, the shared shape is real. This is `architect-review`'s rule; this skill exists to catch the moment before copy two.## What is not reuse- A wrapper around one call site that will only ever have one call site.- A re-export with no added behavior.- Reaching into a `utils.ts` grab-bag because it's *there*, when nothing in it is related to the problem.- Pulling in a new dependency to save five lines you could write directly.## Finish the moveDelete the code the reuse replaced. Two implementations of the same job outlive their reason to exist far longer than anyone plans for.## Reviewing for reuseFor every new function, file, or component in a diff, ask what already did this job. Answer with a symbol and a file path, or state plainly that you looked and found nothing.## What this skill is notNot DRY absolutism. Two call sites that happen to share five lines by coincidence, not by concept, are not duplication - forcing them to share a helper couples things that should be free to diverge.

Frequently asked questions