Documentation Style Guide
Apply these principles when writing or reviewing documentation to ensure clarity, consistency, and accessibility for both human readers and LLMs.
Choose the Right Documentation Type First
Style serves a purpose, and the purpose depends on which of the four Diataxis types you are writing. Before applying the conventions below, decide whether the document is a Tutorial (learning), How-To guide (a task), Reference (looking up), or Explanation (understanding) — these are not interchangeable, and mixing them in one document weakens all of them.
To choose, ask the two compass questions: action or cognition? acquisition or application?
| The reader's stance | Type |
|---|
| "I'm learning — guide my hands" | Tutorial |
| "I have a goal — help me reach it" | How-To |
| "I'm working — let me look something up" | Reference |
| "I'm reflecting — help me understand why" | Explanation |
For the full decision procedure, the 2×2 map, the two distinctions that resolve most ambiguity (Tutorial vs. How-To, Reference vs. Explanation), and the quality model, see references/diataxis-compass.md. The type-specific skills (tutorial-docs, howto-docs, reference-docs, explanation-docs) build on the principles in this guide once the type is chosen.
Voice and Tone
Use Second Person
Address the reader directly as "you" rather than "the user" or "developers."
<!-- Good -->
You can configure the API by setting environment variables.
<!-- Avoid -->
The user can configure the API by setting environment variables.
Developers should configure the API by setting environment variables.
Prefer Active Voice
Write sentences where the subject performs the action. Active voice is clearer and more direct.
<!-- Good -->
Create a configuration file in the root directory.
The function returns an array of user objects.
<!-- Avoid -->
A configuration file should be created in the root directory.
An array of user objects is returned by the function.
Be Concise
Cut unnecessary words. Every word should earn its place.
<!-- Good -->
Run the install command.
<!-- Avoid -->
In order to proceed, you will need to run the install command.
<!-- Good -->
This endpoint returns user data.
<!-- Avoid -->
This endpoint is used for the purpose of returning user data.
Common phrases to simplify:
| Instead of | Use |
|---|
| in order to | to |
| for the purpose of | to, for |
| in the event that | if |
| at this point in time | now |
| due to the fact that | because |
| it is necessary to | you must |
| is able to | can |
| make use of | use |
Document Structure
Write Clear, Descriptive Headings
Headings should tell readers exactly what the section contains. Avoid clever or vague titles.
<!-- Good -->
## Install the CLI
## Configure Authentication
## Handle Rate Limits
<!-- Avoid -->
## Getting Started (vague)
## The Fun Part (clever)
## Misc (uninformative)
Create Self-Contained Pages
Assume readers may land on any page directly from search. Each page should:
- Explain what the feature/concept is
- State prerequisites clearly
- Provide complete context for the topic
<!-- Good: Self-contained -->
# Webhooks
Webhooks let you receive real-time notifications when events occur in your account.
## Prerequisites
- An active API key with webhook permissions
- A publicly accessible HTTPS endpoint
## Create a Webhook
...
Use Semantic Markup
Choose the right format for the content type:
- Headings: Follow proper hierarchy (h1 > h2 > h3, never skip levels)
- Lists: Use for multiple related items
- Tables: Use for structured data with consistent attributes
- Code blocks: Use for any code, commands, or file paths
<!-- Good: Table for structured data -->
| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| api_key | string | Yes | Your API key |
| timeout | integer | No | Request timeout in seconds |
<!-- Good: List for steps or options -->
To authenticate, you can:
- Use an API key in the header
- Use OAuth 2.0
- Use a service account
Make Content Skimmable
Break dense paragraphs into digestible chunks:
- Keep paragraphs to 3-4 sentences maximum
- Use bullet points for lists of items
- Add subheadings to long sections
- Put key information first (inverted pyramid)
<!-- Good: Skimmable -->
## Error Handling
The API returns standard HTTP status codes.
### Common Errors
- **400 Bad Request**: Invalid parameters. Check the request body.
- **401 Unauthorized**: Invalid or missing API key.
- **429 Too Many Requests**: Rate limit exceeded. Wait and retry.
### Retry Strategy
For 429 errors, use exponential backoff starting at 1 second.
Consistency
Use One Term Per Concept
Pick a term and use it consistently. Switching terms confuses readers.
<!-- Good: Consistent terminology -->
Generate an API key in the dashboard. Use your API key in the Authorization header.
<!-- Avoid: Inconsistent terminology -->
Generate an API key in the dashboard. Use your API token in the Authorization header.
Document your terminology choices:
| Concept | Use | Don't use |
|---|
| Authentication credential | API key | API token, secret key, access key |
| Configuration file | config file | settings file, preferences file |
| Command line | CLI | terminal, command prompt, shell |
Apply Consistent Formatting
Use the same formatting for similar content types:
- UI elements: Bold (Click Save)
- Code/commands: Backticks (
npm install)
- File paths: Backticks (
/etc/config.yaml)
- Key terms on first use: Bold or italics
- Placeholders: SCREAMING_CASE or angle brackets (
YOUR_API_KEY or <api-key>)
LLM-Friendly Patterns
State Prerequisites Explicitly
List what users need before starting. This helps both humans and LLMs understand context.
## Prerequisites
Before you begin, ensure you have:
- Node.js 18 or later installed
- An active account with admin permissions
- Your API key (find it in **Settings > API**)
Define Acronyms on First Use
Spell out acronyms the first time they appear on a page.
<!-- Good -->
The CLI (Command Line Interface) provides tools for managing your resources.
Subsequent uses can just say "CLI."
<!-- Avoid -->
The CLI provides tools for managing your resources.
Provide Complete, Runnable Code Examples
Code examples should work when copied. Include:
- All necessary imports
- Realistic placeholder values
- Expected output (when helpful)
<!-- Good: Complete example -->
```python
import requests
API_KEY = "your-api-key"
BASE_URL = "https://api.example.com/v1"
response = requests.get(
f"{BASE_URL}/users",
headers={"Authorization": f"Bearer {API_KEY}"}
)
print(response.json())
# Output: {"users": [{"id": 1, "name": "Alice"}, ...]}
<!-- Avoid: Incomplete snippet -->
response = requests.get(url, headers=headers)
### Write Descriptive Titles and Meta Descriptions
Page titles and descriptions help with search and LLM understanding.
```markdown
---
title: "Authentication - API Reference"
description: "Learn how to authenticate API requests using API keys, OAuth 2.0, or service accounts."
---
Pitfalls to Avoid
Don't Use Product-Centric Language
Orient documentation around user goals, not product features.
<!-- Good: User-goal oriented -->
# Send Emails
Send transactional emails to your users with delivery tracking.
<!-- Avoid: Product-centric -->
# Email Service
Our powerful email service provides enterprise-grade delivery.
Skip Obvious Instructions
Don't document self-explanatory UI actions.
<!-- Good: Meaningful instruction -->
Enter your webhook URL. The URL must use HTTPS and be publicly accessible.
<!-- Avoid: Obvious instruction -->
Click in the text field. Type your webhook URL. Click the Save button.
Avoid Colloquialisms
Colloquialisms hurt clarity and localization.
<!-- Good -->
This approach significantly improves performance.
<!-- Avoid -->
This approach is a game-changer for performance.
This will blow your mind.
Let's dive in!
Two Kinds of Quality
Good documentation has two layers of quality, and the second depends on the first:
- Functional quality — objective and measurable: accuracy, completeness, consistency, usefulness, precision. This is the prerequisite. The principles in this guide and the type-specific skills target functional quality.
- Deep quality — subjective and human-centred: it feels good to use, anticipates the reader, and fits how people actually work. You cannot reach it without functional quality first; choosing the right type (above) and writing it cleanly lays the conditions for it.
See references/diataxis-compass.md for the full quality model and the "work by improvement" approach (improve one real piece at a time; never build empty section skeletons).
Quick Reference Checklist
When writing documentation, verify:
Applying This Skill
Use these principles when:
- Writing new documentation: Apply all principles from the start
- Reviewing documentation: Check against the quick reference checklist
- Editing existing docs: Prioritize voice/tone, then structure, then consistency
- Creating code examples: Ensure they are complete and runnable