Clear Writing

Write with clarity and force. This skill covers what to do (Strunk's rules), how to structure technical documentation (Divio patterns, templates), and what not to do (AI anti-patterns, doc anti-patterns).

When to Use

Use this skill whenever you write prose for humans:

• Documentation, README files, technical explanations
• API documentation, endpoint references, integration guides
• Tutorials, how-to guides, architecture docs
• Commit messages, pull request descriptions
• Error messages, UI copy, help text, comments
• Reports, summaries, or any explanation
• Editing existing prose to improve clarity

If you're writing sentences for a human to read, use this skill.

Limited Context Strategy

When context is tight:

1. Write your draft using judgment
2. Dispatch a subagent with your draft and the relevant reference file
3. Have the subagent copyedit and return the revision

Loading a single reference (~1,000–4,500 tokens) instead of the full skill saves significant context.

Elements of Style

William Strunk Jr.'s The Elements of Style (1918) teaches you to write clearly and cut ruthlessly.

Rules

Elementary Rules of Usage (Grammar/Punctuation):

1. Form possessive singular by adding 's
2. Use comma after each term in series except last
3. Enclose parenthetic expressions between commas
4. Comma before conjunction introducing co-ordinate clause
5. Don't join independent clauses by comma
6. Don't break sentences in two
7. Participial phrase at beginning refers to grammatical subject

Elementary Principles of Composition:

1. One paragraph per topic
2. Begin paragraph with topic sentence
3. Use active voice
4. Put statements in positive form
5. Use definite, specific, concrete language
6. Omit needless words
7. Avoid succession of loose sentences
8. Express co-ordinate ideas in similar form
9. Keep related words together
10. Keep to one tense in summaries
11. Place emphatic words at end of sentence

Reference Files

For complete explanations with examples:

| Section | File | ~Tokens |

|---------|------|---------|

| Grammar, punctuation, comma rules | references/elements-of-style/02-elementary-rules-of-usage.md | 2,500 |

| Paragraph structure, active voice, concision | references/elements-of-style/03-elementary-principles-of-composition.md | 4,500 |

| Headings, quotations, formatting | references/elements-of-style/04-a-few-matters-of-form.md | 1,000 |

| Word choice, common errors | references/elements-of-style/05-words-and-expressions-commonly-misused.md | 4,000 |

Most tasks need only 03-elementary-principles-of-composition.md — it covers active voice, positive form, concrete language, and omitting needless words.

AI Writing Patterns to Avoid

LLMs regress to statistical means, producing generic, puffy prose. Avoid:

• Puffery: pivotal, crucial, vital, testament, enduring legacy
• Empty "-ing" phrases: ensuring reliability, showcasing features, highlighting capabilities
• Promotional adjectives: groundbreaking, seamless, robust, cutting-edge
• Overused AI vocabulary: delve, leverage, multifaceted, foster, realm, tapestry
• Formatting overuse: excessive bullets, emoji decorations, bold on every other word

Be specific, not grandiose. Say what it actually does.

For comprehensive research on why these patterns occur, see references/signs-of-ai-writing.md. Wikipedia editors developed this guide to detect AI-generated submissions — their patterns are well-documented and field-tested.

Document Types (Divio Framework)

| Type | Purpose | Structure |

|------|---------|-----------|

| README | First impression, project overview | Title, description, quick start, install, usage |

| Tutorial | Learning-oriented, guided experience | Numbered steps with expected outcomes |

| How-to Guide | Task-oriented, solve a specific problem | Problem statement → steps → result |

| Reference | Information-oriented, complete and accurate | Alphabetical or grouped, consistent format |

| Explanation | Understanding-oriented, context and rationale | Narrative prose, diagrams, history |

| Architecture Doc | System design, component relationships | Context → components → data flow → decisions |

| API Documentation | Endpoint contracts, integration guide | Endpoint → params → request → response → errors |

Structure Patterns

Inverted Pyramid

Lead with the most important information. Each subsequent section adds detail.

1. What it does (one sentence)
2. How to use it (quick start)
3. Configuration options
4. Advanced usage
5. Internals / implementation details

Problem-Solution

1. Problem — what goes wrong, symptoms, error messages
2. Cause — why it happens (brief)
3. Solution — step-by-step fix
4. Prevention — how to avoid it in the future

Sequential Steps

Every step is a single action with a verifiable outcome.

1. Step — one action, one verb
   Expected result: what the reader should see
2. Step — next action
   Expected result: confirmation of success

Writing Rules

| Rule | Guideline | Example |

|------|-----------|---------|

| Short sentences | Keep under 25 words | "The server restarts automatically after config changes." |

| Active voice | Subject does the action | "The function returns a promise" not "A promise is returned" |

| Present tense | Describe current behavior | "This endpoint accepts JSON" not "will accept JSON" |

| One idea per paragraph | Each paragraph has one point | Split compound paragraphs at the topic shift |

| Define jargon on first use | Never assume vocabulary | "The ORM (Object-Relational Mapper) translates..." |

| Second person | Address the reader directly | "You can configure..." not "One can configure..." |

| Consistent terminology | Pick one term and stick with it | Don't alternate between "repo" and "repository" |

| Concrete over abstract | Specifics beat generalities | "Returns a 404 status code" not "Returns an error" |

Code Examples in Documentation

Every code example must follow these rules:

1. Complete and runnable — copy-paste and execute without modification
2. Annotated — comments on the non-obvious parts, not the obvious ones
3. Progressive complexity — simplest case first, then advanced usage
4. Language-tagged — always specify the language in fenced code blocks
5. Current — examples must work with the documented version
6. Minimal — show only what is relevant; strip unrelated boilerplate

# Good: complete, annotated, minimal
import httpx

# Create a client with a base URL to avoid repeating it
client = httpx.Client(base_url="https://api.example.com")

# Fetch a user by ID — returns a User dict or raises for 4xx/5xx
response = client.get("/users/42")
response.raise_for_status()
user = response.json()
print(user["name"])  # "Ada Lovelace"

README Template

# Project Name

One-line description of what this project does and who it is for.

## Quick Start

The fastest path from zero to working. Three commands or fewer.

## Installation

Prerequisites, system requirements, and step-by-step install.

## Usage

Common use cases with code examples. Cover the 80% case.

## API

Public API surface — functions, classes, CLI flags, endpoints.

## Configuration

Environment variables, config files, and their defaults.

## Contributing

How to set up the dev environment, run tests, and submit changes.

## License

License name and link to the full LICENSE file.

README rules:

• Keep the quick start under 60 seconds of reader time
• Include a badge row only if badges are kept current
• Link to deeper docs rather than bloating the README
• Update the README whenever the public interface changes

API Documentation Pattern

Document every endpoint with this structure:

### GET /users/:id

Retrieve a single user by their unique identifier.

**Authentication:** Bearer token required

**Path Parameters:**

| Parameter | Type   | Required | Description          |
|-----------|--------|----------|----------------------|
| id        | string | Yes      | The user's unique ID |

**Response: 200 OK**

{json response example}

**Error Responses:**

| Status | Code         | Description              |
|--------|--------------|--------------------------|
| 401    | UNAUTHORIZED | Missing or invalid token |
| 404    | NOT_FOUND    | User does not exist      |

Always document errors with: HTTP status, machine-readable error code, human-readable message, and resolution steps.

Audience Adaptation

| Audience | Context Level | Focus | Tone |

|----------|--------------|-------|------|

| Beginner | High — define terms, explain prerequisites | What and how, step by step | Encouraging, patient |

| Intermediate | Medium — assume basic knowledge | How and best practices | Direct, practical |

| Expert | Low — skip fundamentals | Why, edge cases, tradeoffs | Concise, precise |

Rules:

• State the assumed audience at the top of the document
• Link to prerequisite knowledge rather than re-explaining it
• Use expandable sections (
  ) for beginner context in expert docs
• Never mix audience levels in the same section

Review Checklist

Before publishing any documentation:

• [ ] Accurate — all code examples run, all commands work, all links resolve
• [ ] Complete — covers setup, happy path, error cases, and cleanup
• [ ] Consistent — terminology, formatting, and voice match the rest of the docs
• [ ] Readable — passes a cold read by someone unfamiliar with the project
• [ ] Scannable — headings, tables, and lists allow skimming for answers
• [ ] Examples work — every code block tested against the current version
• [ ] Links valid — no broken internal or external links
• [ ] Audience-appropriate — context level matches the stated audience
• [ ] Up to date — no references to deprecated features or old versions
• [ ] Spellchecked — no typos, no inconsistent capitalization

Documentation Anti-Patterns

| Anti-Pattern | Problem | Fix |

|--------------|---------|-----|

| Wall of text | Readers bounce | Break into sections with headings and lists |

| Outdated docs | Erodes trust | Tie doc updates to PR checklists; date-stamp pages |

| No examples | Readers can't apply abstract descriptions | Add code examples for every public function |

| Assumed knowledge | Excludes beginners | Define terms on first use, link to prerequisites |

| Copy-paste unfriendly | Code with $ prompts or line numbers breaks when pasted | Provide clean, runnable code blocks |

| Screenshot-only instructions | Can't be searched, go stale, inaccessible | Pair screenshots with text and commands |

NEVER Do

1. NEVER publish docs without testing every code example — broken examples destroy credibility faster than anything else
2. NEVER write docs after the fact as an afterthought — write docs alongside the code; if you cannot explain it, the design needs work
3. NEVER use "simply", "just", or "obviously" — these words shame readers who are struggling and add no information
4. NEVER mix multiple audiences in one document — write separate beginner and advanced guides, or use clear section boundaries
5. NEVER leave placeholder text in published docs — "TODO", "TBD", and "lorem ipsum" signal abandonment
6. NEVER duplicate content across documents — link to a single source of truth; duplicates inevitably drift apart
7. NEVER omit the date or version — readers must know if they are looking at current information
8. NEVER use AI puffery words — pivotal, crucial, seamless, robust, groundbreaking, tapestry, and their ilk add nothing and signal lazy writing