Red Pencil Editor — Agent Skills
The AI that marks but never fixes.
Most AI writing tools rewrite your sentences for you. That's the problem. The learning happens when you do the revision, not when a model launders your draft into fluent prose you didn't write.
Red Pencil Editor flips it. The AI marks errors, flags weak claims, points to high-leverage spots — and then stops. You diagnose. You fix. The red pencil tells you where and what kind, never how. That's why it's compatible with "no AI rewriting" pledges: it diagnoses without ghostwriting.
This repo packages the two Red Pencil modes as installable Agent Skills so they trigger automatically in Claude, Codex, Cursor, Gemini, or any tool that reads the standard.
The two modes
| Skill | What it does | Use it when |
|---|---|---|
| professor-mode | Engages with argument, structure, and style. Circles every error, flags weak and strong moments, marks premium real estate, adds at most three short strategic notes. Never rewrites. | You want substantive feedback on a draft and still want to do the revision yourself. |
| editor-mode | Pure copyediting. Circles objective errors only — spelling, grammar, punctuation, typos. Zero commentary. Assumes every style choice is intentional. | You want proofreading for correctness with no opinion on your ideas or structure. |
Pick the specialist that matches the job. Professor Mode pushes you to think harder; Editor Mode just catches the mechanical mistakes and gets out of the way.
Install
npx skills add justinneuman-coder/red-pencil-editor-skills
That installs both modes. The agent reads each skill's description and fires the right one based on what you ask.
Manual install (fallback)
Clone the repo and copy the skill folders into your tool's skills directory:
git clone https://github.com/justinneuman-coder/red-pencil-editor-skills.git
cp -r red-pencil-editor-skills/professor-mode /path/to/your/skills/
cp -r red-pencil-editor-skills/editor-mode /path/to/your/skills/
(Skills directory location varies by tool — check your tool's docs for where it looks.)
How to use it
- Write your draft.
- Ask your AI to review it. Say "give me feedback on this draft" (Professor Mode) or "just proofread this, no commentary" (Editor Mode) — the right skill fires.
- For Professor Mode, specify your level: "I'm in high school" or "I'm in college."
- Get your marked-up essay.
- Do the revision work yourself.
Details
- Free. MIT licensed.
- Model-agnostic. Works with any text-based AI that supports Agent Skills.
- Privacy. Your essay text goes to whatever AI tool you've installed the skill in. The skill itself is just a prompt — it stores nothing and phones home to nothing.
Built by Justin Neuman, Professor of Literary Studies at The New School.
The full web version (paste-and-go prompts, marked-up PDF output, demo) lives at red-pencil-editor.com.
More tools: ultra-normal.com · academicvelocity.com