AI-powered smart replies for WhatsApp Web and Facebook Messenger using Google Gemini API.

• Semi-Auto Reply Mode - Click "✨ Reply with AI" button to generate contextual replies
• Multi-Platform Support - Works with WhatsApp Web, Facebook Messenger, and Facebook chat popups
• Conversation Context - Sends up to 15 recent messages to Gemini for contextual replies
• Keyword Rules - Set up automatic replies for specific keywords/phrases
• Custom System Prompt - Personalize AI behavior and tone
• Webhook Integration - Send conversation data to external CRM/systems
• Smart Input Detection - Automatically finds and types into chat input boxes

1. Open Chrome and navigate to chrome://extensions/
2. Enable Developer mode (toggle in top-right corner)
3. Click Load unpacked
4. Select the ai-auto-reply-extension folder
5. The extension icon should appear in your toolbar

Coming soon

1. Get a Gemini API Key:

   • Visit Google AI Studio
   • Create a new API key
   • Copy the key

2. Configure Extension:

   • Click the extension icon in Chrome toolbar
   • Paste your Gemini API Key
   • Toggle "Enable Auto Reply" ON
   • Customize settings (optional)

3. Start Using:

   • Open WhatsApp Web or Facebook Messenger
   • You'll see a green "✨ Reply with AI" button at bottom-right
   • Click it anytime to generate a contextual reply

1. Click the button → Extension collects conversation history
2. AI analyzes context → Sends to Gemini API with full conversation
3. Reply typed → AI-generated text appears in input box
4. You review & send → Manually press Enter to send

The extension sends conversation history to Gemini in this structured format:

ROLE: You are a helpful customer support assistant...

CONVERSATION HISTORY (most recent messages, in order):
────────────────────────────────────
👤 Customer: Hello, do you have this in stock?
🤖 You: Yes, we have it available. Would you like to order?
👤 Customer: How much is shipping?
────────────────────────────────────

TASK: The customer's latest message is: "How much is shipping?"
Write a natural reply based on the full conversation above.

RULES:
- Reply in the SAME LANGUAGE the customer is using
- Keep it brief and conversational (1-3 sentences)
- Be contextually relevant to what was discussed
- Do NOT include any label, prefix, or emoji at the start
- Just output the reply text, nothing else

Set up automatic replies for common queries:

Send conversation data to external systems:

• Webhook URL - Your endpoint to receive message data
• Trigger - Sends data when AI reply is generated

┌─────────────┐     ┌──────────────┐     ┌─────────────────┐
│  Popup UI   │────▶│ Background   │────▶│  Gemini API     │
│  (settings) │     │  (service    │     │  (Google AI)    │
└─────────────┘     │   worker)    │     └─────────────────┘
       │            └──────────────┘              ▲
       │                   ▲                      │
       ▼                   │                      │
┌─────────────┐           │              ┌──────┴──────────┐
│ Content     │───────────┘              │  Reply Text     │
│ Script      │  (GET_AI_REPLY)          │  (typed to UI)  │
│ (WhatsApp/  │◀──────────────────────────┘                 │
│  Facebook)  │                                           │
└─────────────┘                                           │
       ▲                                                  │
       │                                                  │
       └──────────────────────────────────────────────────┘

ai-auto-reply-extension/
├── manifest.json       # Extension manifest (v3)
├── background.js       # Service worker - API calls, webhooks
├── content.js          # Content script - UI injection, chat detection
├── popup.html          # Extension popup UI
├── popup.js            # Popup logic
├── styles.css          # Popup styling
├── icons/
│   ├── icon16.png      # Toolbar icon (16x16)
│   ├── icon48.png      # Extension icon (48x48)
│   └── icon128.png     # Store icon (128x128)
└── README.md           # This file

• storage - Save settings locally
• activeTab - Access current tab for debugging
• scripting - Inject content scripts
• tabs - Query and message all tabs
• host_permissions:
  • web.whatsapp.com/* - WhatsApp Web access
  • facebook.com/* - Facebook Messenger access
  • messenger.com/* - Messenger access
  • generativelanguage.googleapis.com/* - Gemini API

1. Make sure you're on facebook.com (not messenger.com)
2. Open a chat popup by clicking a conversation
3. Look for the green "✨ Reply with AI" button at bottom-right
4. If missing, refresh the page (F5)

1. Extension was updated/reloaded
2. Solution: Refresh the page (F5)

1. Click inside the chat input box first
2. Then click "Reply with AI" button
3. If still failing, try refreshing the page

1. Click extension icon in toolbar
2. Enter your Gemini API key in the settings
3. Toggle "Enable Auto Reply" ON
4. Refresh WhatsApp/Messenger page

1. Clone or download the extension folder
2. Load unpacked in Chrome (see Installation)
3. Edit files and reload extension to test changes

Open browser console (F12 → Console) and filter by [AI Auto Reply] to see debug logs.

// Check if content script loaded
console.log('[AI Auto Reply]', 'Manual test');

// Find input box manually
document.querySelectorAll('div[contenteditable="true"]');

• API Key Storage: Your Gemini API key is stored locally in Chrome's storage (not sent to any server)
• Conversation Data: Messages are sent to Google's Gemini API for generating replies
• Webhook Data: Only sent if you configure a webhook URL
• No Analytics: Extension does not track usage or send analytics

MIT License - Feel free to modify and distribute.

• Initial release
• WhatsApp Web support
• Facebook Messenger support
• Facebook chat popup support
• Semi-auto "Reply with AI" button
• Conversation context for Gemini
• Keyword rules
• Webhook integration
• Custom system prompts

For issues or feature requests:

1. Check the Troubleshooting section above
2. Review console logs for error messages
3. Ensure API key is valid and has quota remaining

Made with ❤️ for smarter conversations