docs

name	docs
description	Add or improve documentation for code. Use when code needs JSDoc comments, inline explanations, README files, or documentation updates.
category	meta
triggers	["add documentation","needs docs","document this","JSDoc","README"]

Docs

Purpose: Add or improve documentation for code Usage: /docs [scope flags] <description>

Iron Laws

1. DOCUMENTATION ONLY -- Do not change code behavior. If you spot a bug while documenting, note it — don't fix it.
2. EXPLAIN THE WHY -- Self-evident code needs no comment. When you do comment, explain the reasoning, not the mechanics.
3. DO NOT GUESS INTENT -- If you're unsure why code exists or what it does, ask. Wrong documentation is worse than no documentation.

Note: Command examples use npm as default. Adapt to the project's package manager per ai-assistant-protocol — Project Commands.

When to Use

• Exported functions or classes lack JSDoc
• Complex algorithms or business logic need explanation
• A package or module has no README
• Public APIs need usage examples
• After implementing a feature that changes the API surface

When NOT to Use

• Adding test coverage for code -> /test-coverage
• Exploring code to understand it -> /explore
• Recording an architecture decision -> /adr
• Documenting deferred work or tech debt -> /add-todo
• Writing a full project README from scratch -> /init

Scope Flags

Flag	Description
--files=<paths>	Document only specified files/directories

Examples:

/docs --files=src/utils/       # Document all utils
/docs --files=src/api/client.ts  # Document specific file
/docs add JSDoc to exported functions

Workflow

Step 1: Identify Documentation Scope

Determine what needs documentation:

# Find files without JSDoc comments
# Look for exported functions/classes

# Check for missing README files
find . -type d -name "src" -exec test ! -f {}/README.md \; -print

Target areas:

• Exported functions and classes
• Complex algorithms or business logic
• Public APIs and interfaces
• Package/module entry points

If all exported functions, classes, and interfaces already have complete, accurate JSDoc: Report "Documentation is complete — no changes needed" and exit.

Step 2: Analyze Code Purpose

Before documenting, understand:

• What does this code do?
• Why does it exist?
• How is it used?
• What are the edge cases?

Read the implementation and any existing tests to understand behavior.

Finding test files: Look for tests in common locations:

• __tests__/ directory adjacent to the source file
• .spec.ts or .test.ts suffix next to the source file
• tests/ directory at the project root

Step 3: Add Documentation

For Functions (JSDoc):

/**
 * Brief description of what the function does.
 *
 * @param paramName - Description of the parameter
 * @returns Description of the return value
 * @throws {ErrorType} Description of when this error is thrown
 *
 * @example
 * ```typescript
 * const result = functionName(input);
 * ```
 */
export function functionName(paramName: Type): ReturnType {
  // ...
}

For Classes:

/**
 * Brief description of the class purpose.
 *
 * @example
 * ```typescript
 * const instance = new ClassName(config);
 * instance.method();
 * ```
 */
export class ClassName {
  // ...
}

For Interfaces and Type Aliases:

/**
 * Brief description of the interface purpose.
 * Explain when this type is used and any important constraints.
 *
 * @example
 * ```typescript
 * const config: InterfaceName = { key: 'value' };
 * ```
 */
export interface InterfaceName {
  /** Description of this property */
  propertyName: Type;
}

For Complex Logic (Inline Comments):

// Explain WHY, not WHAT
// Good: "Skip validation for internal calls to avoid circular dependency"
// Bad: "Check if internal is true"
if (isInternal) {
  return data;
}

For Modules/Packages (README.md):

# Module Name

Brief description of module purpose.

## Usage

\`\`\`typescript
import { something } from './module';
\`\`\`

## API

### `functionName(param)`

Description of the function.

Step 4: Documentation Standards

Do:

• Explain the "why" behind decisions
• Include usage examples
• Document edge cases and gotchas
• Keep descriptions concise but complete
• Use consistent terminology

Don't:

• State the obvious ("Increments counter by 1")
• Document implementation details that may change
• Add comments to self-explanatory code
• Use vague descriptions ("Handles stuff")

Step 4.5: Confirm Documentation Changes

Present a summary of planned documentation changes before applying:

## Planned Documentation Changes

| File | Change |
|------|--------|
| `src/services/payment.service.ts` | Add JSDoc to `processPayment()`, `getPaymentStatus()` |
| `src/services/payment.service.ts` | Update stale JSDoc on `refundPayment()` |
| `src/services/payment.service.ts` | Add interface docs for `PaymentConfig` |

**Apply these changes?** (yes / edit / cancel)

GATE: User must approve documentation plan before changes are applied.

Step 5: Verify Documentation

After adding documentation:

• Ensure examples compile/work
• Check for spelling/grammar
• Verify accuracy against implementation
• Run type check to catch JSDoc type issues

npm run typecheck

Step 6: Present Documentation Report

Present the documentation report using the Output Format defined below. Include what was added, updated, and skipped.

Rules

Prohibited

• Do not add noise documentation -- Comments that restate the obvious
• Do not document every line -- Only add value where needed
• Do not guess at intent -- Ask if unclear about purpose

Required

• JSDoc for exported functions -- Public API must be documented
• Examples for complex usage -- Show how to use non-obvious APIs
• README for packages -- Each package/module should have one

Recommended

• Document edge cases -- What happens with null, empty, etc.
• Link related code -- Reference related functions or modules
• Update stale docs -- Fix outdated documentation when found

Output Format

Report what was documented:

## Documentation Report

### Files Updated
- `src/utils/parser.ts` - Added JSDoc to 3 functions
- `src/services/api.ts` - Added module description
- `src/components/README.md` - Created package README

### Documentation Added
- `parseConfig()` - Function description, params, return, example
- `ApiService` - Class description, usage example
- `src/components/` - README with usage and API docs

### Notes
- `legacyHandler()` - Skipped, marked for deprecation
- Consider adding architecture docs for data flow

Quick Reference

JSDoc Tags

Tag	Purpose	Example
@param	Parameter description	@param name - User's display name
@returns	Return value	@returns The parsed configuration
@throws	Exceptions	@throws {Error} If config is invalid
@example	Usage example	See code block examples above
@deprecated	Mark as deprecated	@deprecated Use newFunction instead
@see	Reference related	@see parseConfig

Documentation Checklist

• Exported functions have JSDoc
• Complex logic has explanatory comments
• Public APIs have examples
• Packages have README files
• Edge cases are documented
• Examples are accurate and tested

Acceptance Tests

ID	Type	Prompt / Condition	Expected
DOC-T1	Positive	"Add JSDoc to this file"	Skill triggers
DOC-T2	Positive	"Document the public API"	Skill triggers
DOC-T3	Positive	"This module needs a README"	Skill triggers
DOC-T4	Negative	"Add tests for this code"	Does NOT trigger (-> /test-coverage)
DOC-T5	Negative	"How does this work?"	Does NOT trigger (-> /explore)
DOC-T6	Negative	"Record why we chose this approach"	Does NOT trigger (-> /adr)
DOC-T7	Boundary	"Explain this function"	Context-dependent — if user wants docs added, trigger; if exploring to understand, route to /explore
DOC-T8	Positive	/docs --files=src/services/payment.service.ts	Skill triggers, scopes to the specified file
DOC-T9	Positive	"Update the stale JSDoc on this function"	Skill triggers — stale doc update is in scope
DOC-T10	Positive	"Document this interface"	Skill triggers — interface documentation is in scope
DOC-T11	Negative	"Document this private helper"	Does NOT document — private/non-exported helpers are out of scope
DOC-T12	Boundary	"Add @throws tags to error-throwing functions"	Skill triggers — @throws documentation is in scope
DOC-T13	Early-exit	All exports already have complete JSDoc	Reports "Documentation is complete — no changes needed" and exits