chrome-extension

name	chrome-extension
description	Expert guidance for Chrome extension development with Manifest V3. Use when building Chrome extensions, browser extensions, or working with Chrome APIs. Triggers on: chrome extension, browser extension, manifest v3, chrome api, extension development.

Chrome Extension Development

Expert guidance for Chrome extension development with Manifest V3.

Code Style and Structure

• Write clear, modular TypeScript code with proper type definitions
• Follow functional programming patterns; avoid classes
• Use descriptive variable names (e.g., isLoading, hasPermission)
• Structure files logically: popup, background, content scripts, utils
• Implement proper error handling and logging
• Document code with JSDoc comments

Architecture and Best Practices

• Strictly follow Manifest V3 specifications
• Divide responsibilities between background, content scripts and popup
• Configure permissions following the principle of least privilege
• Use modern build tools (webpack/vite) for development
• Implement proper version control and change management

Chrome API Usage

Storage

// Save data
chrome.storage.local.set({ key: value });

// Read data
const { key } = await chrome.storage.local.get('key');

// Listen for changes
chrome.storage.onChanged.addListener((changes, namespace) => {
  if (changes.key) {
    console.log('Key changed:', changes.key.newValue);
  }
});

Tabs

// Create tab
const tab = await chrome.tabs.create({ url: 'https://example.com' });

// Query tabs
const tabs = await chrome.tabs.query({ active: true, currentWindow: true });

// Send message to tab
await chrome.tabs.sendMessage(tabId, { action: 'update' });

Runtime (Messaging)

// Background script
chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
  if (message.action === 'getData') {
    sendResponse({ data: 'response' });
  }
  return true; // Keep channel open for async response
});

// Content/Popup script
const response = await chrome.runtime.sendMessage({ action: 'getData' });

Alarms (Scheduled Tasks)

// Create alarm
chrome.alarms.create('myAlarm', { periodInMinutes: 30 });

// Listen for alarm
chrome.alarms.onAlarm.addListener((alarm) => {
  if (alarm.name === 'myAlarm') {
    // Execute task
  }
});

Security and Privacy

• Implement Content Security Policy (CSP)
• Handle user data securely
• Prevent XSS and injection attacks
• Use secure messaging between components
• Handle cross-origin requests safely
• Implement secure data encryption
• Follow web_accessible_resources best practices

Performance and Optimization

• Minimize resource usage and avoid memory leaks
• Optimize background script performance
• Implement proper caching mechanisms
• Handle asynchronous operations efficiently
• Monitor and optimize CPU/memory usage

Manifest V3 Structure

{
  "manifest_version": 3,
  "name": "My Extension",
  "version": "1.0.0",
  "permissions": ["storage", "activeTab"],
  "background": {
    "service_worker": "background.js"
  },
  "content_scripts": [{
    "matches": ["<all_urls>"],
    "js": ["content.js"]
  }],
  "action": {
    "default_popup": "popup.html"
  }
}

Testing and Debugging

• Use Chrome DevTools effectively
• Write unit and integration tests
• Test cross-browser compatibility
• Monitor performance metrics
• Handle error scenarios

Publishing Checklist

• Prepare store listings and screenshots
• Write clear privacy policies
• Implement update mechanisms
• Handle user feedback
• Maintain documentation

Activation Keywords

• chrome-extension
• chrome-extension
• chrome extension

Tools Used

• exec
• read
• write
• edit

Instructions for Agents

1. Read the task description carefully
2. Follow the step-by-step process
3. Use the appropriate tools
4. Verify the results

Examples

Example 1: Basic Usage

User:

Agent:

Example 2: Advanced Usage

User:

Agent: