AI Documentation Tools: ให้ AI ช่วยเขียน Documentation

Documentation เป็นส่วนสำคัญที่มักถูกละเลย AI สามารถช่วยเขียน docs ได้รวดเร็วและมีคุณภาพ ทำให้ code เข้าใจง่ายขึ้น

ทำไมต้องใช้ AI เขียน Documentation?

ปัญหาของ Documentation แบบดั้งเดิม

Traditional Documentation:
- ใช้เวลามาก
- มักถูกข้าม
- Outdated เร็ว
- ไม่ consistent
- น่าเบื่อในการเขียน

AI-Assisted Documentation

AI Documentation:
✅ เขียนได้รวดเร็ว
✅ Consistent format
✅ ครอบคลุมทุกส่วน
✅ ปรับ update ง่าย
✅ หลายภาษา/หลายระดับ

Types of Documentation

1. Code Comments

// AI สามารถสร้าง comments ที่อธิบาย:
// - What: function ทำอะไร
// - Why: ทำไมต้องเขียนแบบนี้
// - How: ทำงานอย่างไร
// - Parameters & Return values

2. README Files

README ที่ดีควรมี:
- Project overview
- Installation steps
- Usage examples
- Configuration
- Contributing guide

3. API Documentation

API Docs ที่ครบถ้วน:
- Endpoint descriptions
- Request/Response schemas
- Examples
- Error codes
- Authentication

4. Technical Guides

Guides สำหรับ:
- Getting started
- Architecture overview
- Best practices
- Troubleshooting

Practical Examples

Example 1: Function Documentation

// ก่อน: ไม่มี documentation
function calculateShipping(items, address, options) {
  let weight = items.reduce((sum, item) => sum + item.weight * item.qty, 0);
  let base = weight * 0.5;

  if (address.country !== 'TH') {
    base *= 2.5;
  }

  if (options.express) {
    base *= 1.5;
  }

  if (weight > 10) {
    base *= 0.9;
  }

  return Math.round(base * 100) / 100;
}

Prompt:
"Add comprehensive JSDoc documentation to this function.
Include @description, @param, @returns, and @example"

// หลัง: มี documentation ครบถ้วน
/**
 * Calculates shipping cost based on items, destination, and shipping options.
 *
 * @description
 * This function computes the shipping cost using the following factors:
 * - Total weight of all items
 * - Destination country (international shipping costs 2.5x more)
 * - Express delivery option (1.5x multiplier)
 * - Bulk discount (10% off for orders over 10kg)
 *
 * @param {Array<Object>} items - Array of items to ship
 * @param {number} items[].weight - Weight of single item in kg
 * @param {number} items[].qty - Quantity of this item
 * @param {Object} address - Shipping destination
 * @param {string} address.country - ISO country code (e.g., 'TH', 'US')
 * @param {Object} options - Shipping options
 * @param {boolean} [options.express=false] - Whether to use express delivery
 *
 * @returns {number} Calculated shipping cost in THB, rounded to 2 decimals
 *
 * @example
 * // Domestic standard shipping
 * calculateShipping(
 *   [{ weight: 2, qty: 3 }], // 6kg total
 *   { country: 'TH' },
 *   { express: false }
 * ); // Returns: 3.00
 *
 * @example
 * // International express shipping with bulk discount
 * calculateShipping(
 *   [{ weight: 5, qty: 3 }], // 15kg total
 *   { country: 'US' },
 *   { express: true }
 * ); // Returns: 25.31 (base * 2.5 * 1.5 * 0.9)
 */
function calculateShipping(items, address, options = {}) {
  // ... implementation
}

Example 2: README Generation

Prompt:
"Generate a comprehensive README.md for a React
e-commerce project with the following features:
- Product catalog
- Shopping cart
- User authentication
- Stripe payments
- Admin dashboard

Tech stack: React, TypeScript, Tailwind, Supabase, Stripe

Include all standard sections."

# ShopReact - E-Commerce Platform

A modern, full-featured e-commerce platform built with React and TypeScript.

## 🚀 Features

- **Product Catalog**: Browse and search products with filters
- **Shopping Cart**: Add, remove, and manage items
- **User Authentication**: Secure login/signup with Supabase
- **Payments**: Stripe integration for secure checkout
- **Admin Dashboard**: Manage products, orders, and users

## 📦 Tech Stack

- **Frontend**: React 18, TypeScript
- **Styling**: Tailwind CSS
- **Database**: Supabase (PostgreSQL)
- **Authentication**: Supabase Auth
- **Payments**: Stripe
- **State Management**: Zustand

## 🛠️ Installation

### Prerequisites

- Node.js 18+
- npm or yarn
- Supabase account
- Stripe account

### Setup

1. Clone the repository
   git clone https://github.com/username/shop-react.git
   cd shop-react

2. Install dependencies
   npm install

3. Set up environment variables
   cp .env.example .env.local
   # Edit .env.local with your credentials

4. Run database migrations
   npm run db:migrate

5. Start development server
   npm run dev

## 🔧 Configuration

Create a `.env.local` file with:

NEXT_PUBLIC_SUPABASE_URL=your_supabase_url
NEXT_PUBLIC_SUPABASE_ANON_KEY=your_anon_key
STRIPE_SECRET_KEY=your_stripe_secret
NEXT_PUBLIC_STRIPE_PUBLISHABLE_KEY=your_stripe_public

## 📚 Documentation

- [API Reference](./docs/api.md)
- [Database Schema](./docs/database.md)
- [Deployment Guide](./docs/deployment.md)

## 🤝 Contributing

1. Fork the repository
2. Create a feature branch
3. Commit your changes
4. Push to the branch
5. Open a Pull Request

## 📄 License

MIT License - see [LICENSE](LICENSE) for details

Example 3: API Documentation

Prompt:
"Generate API documentation for this Express endpoint
in OpenAPI/Swagger format"

# AI Generated OpenAPI Spec
openapi: 3.0.0
info:
  title: User Management API
  version: 1.0.0
  description: API for managing user accounts

paths:
  /api/users:
    post:
      summary: Create a new user
      description: |
        Creates a new user account with the provided information.
        Email must be unique. Password is hashed before storage.
      tags:
        - Users
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - email
                - password
                - name
              properties:
                email:
                  type: string
                  format: email
                  example: user@example.com
                password:
                  type: string
                  minLength: 8
                  example: securePassword123
                name:
                  type: string
                  example: John Doe
      responses:
        '201':
          description: User created successfully
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/User'
        '400':
          description: Missing required fields
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '409':
          description: Email already exists
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'

components:
  schemas:
    User:
      type: object
      properties:
        id:
          type: string
          format: uuid
        email:
          type: string
        name:
          type: string
        createdAt:
          type: string
          format: date-time
    Error:
      type: object
      properties:
        error:
          type: string

AI Documentation Tools

GitHub Copilot

Features:
- Inline comment generation
- Docstring completion
- README templates

Usage:
1. Type comment prefix (// or /*)
2. Copilot suggests documentation
3. Tab to accept

Cursor IDE

Built-in documentation:
1. Select code
2. Cmd+K → "Document this code"
3. Get comprehensive docs

Features:
- Context-aware
- Multiple doc styles
- Inline updates

Specialized Tools

1. Mintlify
   - Auto-generate docs from code
   - Beautiful documentation sites
   - AI-powered updates

2. ReadMe
   - API documentation
   - Interactive examples
   - Developer hub

3. Swimm
   - Code-coupled documentation
   - Auto-updates with code changes
   - Team collaboration

Prompt Templates

Code Documentation

"Add documentation to this [language] code:

[paste code]

Include:
- Function/class description
- Parameters with types
- Return values
- Usage examples
- Edge cases noted

Format: [JSDoc/Docstring/XML comments]"

README Generation

"Generate a README.md for this project:

Project: [name]
Description: [what it does]
Tech Stack: [technologies]
Features: [main features]

Include:
- Overview
- Installation
- Configuration
- Usage examples
- Contributing guidelines
- License"

API Documentation

"Generate API documentation for:

[paste API code or describe endpoints]

Format: [OpenAPI/Markdown/Postman collection]

Include:
- Endpoint descriptions
- Request/response schemas
- Example requests
- Error codes and handling
- Authentication requirements"

Best Practices

1. Be Specific About Format

❌ "Document this"

✅ "Add JSDoc documentation with:
- @description
- @param with types
- @returns
- @throws
- @example with actual usage"

2. Specify Audience

"Write documentation for:
- Beginner developers (more explanation)
- API consumers (focus on usage)
- Internal team (include implementation details)"

3. Request Multiple Formats

"Generate documentation in:
1. Inline comments for developers
2. README section for users
3. API reference for integrators"

4. Include Examples

"Add practical examples showing:
- Basic usage
- Advanced patterns
- Common mistakes to avoid
- Real-world scenarios"

Documentation Workflow

Initial Documentation

1. Write code
2. Ask AI to generate docs
3. Review and refine
4. Integrate with code

Maintenance

1. Code changes detected
2. AI suggests doc updates
3. Review changes
4. Approve or modify

Documentation Review

"Review this documentation for:
- Accuracy
- Completeness
- Clarity
- Examples quality
- Consistency with code"

Types of Documentation by Audience

For Users

Focus on:
- Getting started
- Common use cases
- Troubleshooting
- Examples

Prompt:
"Write user documentation assuming no technical
background. Focus on how to use, not how it works."

For Developers

Focus on:
- Architecture
- API reference
- Code examples
- Integration guides

Prompt:
"Write developer documentation with technical
details, code examples, and implementation notes."

For Contributors

Focus on:
- Setup guide
- Code style
- PR process
- Testing requirements

Prompt:
"Write contributor documentation covering
development setup, coding standards, and
contribution workflow."

สรุป

AI Documentation Benefits:

1. Speed: เขียนได้เร็วขึ้นมาก
2. Consistency: Format เดียวกันทั้ง project
3. Coverage: ครบถ้วนไม่ตกหล่น
4. Quality: ภาษาชัดเจน เข้าใจง่าย
5. Maintenance: Update ง่าย

Documentation Types:

• Code comments
• README files
• API documentation
• Technical guides
• User manuals

Best Practices:

• Specify format และ audience
• Include examples
• Review AI output
• Keep docs updated

Remember:

• Documentation = investment
• AI ช่วยลดภาระ
• Review เสมอก่อนใช้
• Update เมื่อ code เปลี่ยน

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อ่านเพิ่มเติม:

• AI Code Review
• AI Testing Automation
• Vibe Coding Best Practices