Use when writing any prose humans will read — documentation, README files, commit messages, error messages, PR descriptions, UI copy, help text, reports, summaries, or explanations. Applies Strunk's timeless rules for clearer, stronger, more professional writing. Use this even for short text like error messages, log messages, or inline comments. If you're writing sentences for a human to read, use this skill.
When context is tight:
Loading a single section (~1,000-4,500 tokens) instead of everything saves significant context.
William Strunk Jr.'s The Elements of Style (1918) teaches you to write clearly and cut ruthlessly.
Elementary Rules of Usage (Grammar/Punctuation):
Elementary Principles of Composition:
The rules above are summarized from Strunk's original text. For complete explanations with examples:
| Section | File | ~Tokens |
|---|---|---|
| Grammar, punctuation, comma rules | elements-of-style/01-elementary-rules-of-usage.md | 2,500 |
| Paragraph structure, active voice, concision | elements-of-style/02-elementary-principles-of-composition.md | 4,500 |
| Headings, quotations, formatting | elements-of-style/03-a-few-matters-of-form.md | 1,000 |
| Word choice, common errors | elements-of-style/04-words-and-expressions-commonly-misused.md | 4,000 |
Most tasks need only elements-of-style/02-elementary-principles-of-composition.md — it covers active voice, positive form, concrete language, and omitting needless words.
After writing, use the humanizer skill to scan for and remove AI writing patterns — puffery, empty phrases, promotional adjectives, overused AI vocabulary, and formatting overuse. The humanizer has a comprehensive, severity-ranked pattern catalog specifically tuned for Claude output.
Writing for humans? Load the relevant section from elements-of-style/ and apply the rules. For most tasks, elements-of-style/02-elementary-principles-of-composition.md covers what matters most.