SessionSwitch

SessionSwitch is a Manifest V3 Chrome extension that intelligently captures your browsing context, groups related tabs into sessions using AI-powered agents, and makes it effortless to resume later. Tab capture happens locally, while a Python FastAPI backend with Google ADK (Agent Development Kit) uses multi-agent reasoning to decide how tabs should be grouped and named.

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Features

• Automatic tab capture: Records URL, title, favicon, timestamps, and extracted page content whenever you switch or finish loading a tab.
• Session heuristics: Detects session boundaries using idle thresholds (default 12 minutes) and significant domain changes.
• Intelligent cleanup: Automatically removes single-tab sessions older than 10 minutes and expires sessions after 24 hours.
• Duplicate suppression: Ignores repeated captures of the same tab/URL within two minutes and detects duplicate tabs across sessions.
• Multi-agent AI system: Uses Google ADK with specialized agents:
  • Summarizer Agent: Analyzes tab content and context with optional web search
  • Matcher Agent: Intelligently groups related tabs with generous merging logic
  • Labeler Agent: Generates concise, descriptive session names
  • Base Agent: Coordinates all agents and returns structured decisions
• Smart session actions: Three decision types - merge into existing session, create new session, or no action (for duplicates)
• Manual snapshots: Save the current window's tabs as a named session from the popup UI.
• Resume & group sessions: Re-open all tabs or create tab groups for any saved session with one click.
• Configurable settings: Adjust idle thresholds, exclude domains, pause capture, and set the server URL from the options page.
• Local persistence: Sessions and settings live in chrome.storage.local; no external database required.

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Directory Structure

session-context/
├── background.js                    # Service worker with optimized helpers
├── manifest.json                    # Extension configuration
├── popup/                           # Extension popup UI
│   ├── popup.html
│   ├── popup.css
│   └── popup.js
├── settings/                        # Settings/options page
│   ├── settings.html
│   ├── settings.css
│   └── settings.js
├── utils/                          # Core utilities (optimized)
│   ├── constants.js                # Central configuration & constants
│   ├── storage.js                  # Chrome storage wrapper
│   ├── sessionizer.js              # Session boundary detection
│   ├── contentExtractor.js         # Page content extraction
│   └── serverAPI.js                # Backend API client
├── icons/                          # Extension icons
│   ├── generate-icons.html
│   ├── icon16.png
│   ├── icon48.png
│   └── icon128.png
└── adk_server/                     # Python FastAPI + Google ADK backend
    ├── main.py                # FastAPI server with /api/group & /api/label
    │   ├── schemas.py             # Pydantic models for requests/responses
    │   ├── base_agent/            # Root coordinator agent
    │   │   ├── agent.py
    │   │   └── tools.py           # Web search & datetime tools
    │   ├── summarizer/            # Tab content summarization agent
    │   │   ├── agent.py
    │   │   └── prompt.py
    │   ├── matcher/               # Session matching agent
    │   │   ├── agent.py
    │   │   └── prompt.py
    │   └── labeler/               # Session label generation agent
    │       ├── agent.py
    │       └── prompt.py
    ├── requirements.txt
    └── .env                       # API keys (OPENAI_API_KEY, SERPER_API_KEY)

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Core Components

Extension

manifest.json

Manifest V3 configuration defining permissions, service worker, popup, and options page.

Background Service Worker (background.js)

Optimized with helper functions and constants:

• Initializes session state on install/startup with 15-second idle detection
• Captures active tabs with shouldSkipTab() validation
• Extracts page content via contentExtractor.js
• Applies session boundary heuristics (idle threshold + domain changes)
• Calls multi-agent backend via serverAPI.js for intelligent grouping
• Handles three decision types: merge, create_new, no_action
• Runs automatic cleanup every 5 minutes for stale sessions
• New helpers: handleServerDecision(), handleNoActionDecision()

Popup (popup/)

• popup.html & popup.css: Modern gradient-themed UI
• popup.js: Session management with Resume, Group, Delete, and manual snapshot features

Settings (settings/)

• Configuration UI for idle threshold, excluded domains, pause capture, and server URL
• Validates inputs and provides quick "Use local server" helper

Utilities (utils/)

Optimized and production-ready:

• constants.js ⭐ NEW: Central configuration (time constants, server config, action types)
• storage.js: Chrome storage wrapper with optimized cleanup logic
• sessionizer.js: Session boundary detection and tab deduplication
• contentExtractor.js: 52% smaller - extracts headings, meta, and body text for AI context
• serverAPI.js: Type-safe API client for backend endpoints

Backend (Python FastAPI + Google ADK)

Multi-Agent Architecture (adk_server/)

The backend uses Google's Agent Development Kit with a coordinator pattern:

Root Agent (base_agent/)

• Orchestrates the entire decision flow
• Delegates to specialized sub-agents
• Returns structured JSON with SessionMatchOutput schema

Summarizer Agent (summarizer/)

• Analyzes tab title, URL, and extracted content
• Uses web_search tool for additional context
• Produces structured summaries with explicit URLs

Matcher Agent (matcher/)

• Compares new tab summary against existing sessions
• Generous merging logic: focuses on broad themes, not exact keywords
• Generates updated labels that reflect both old + new content
• Decides: merge, create_new, or no_action (for duplicates)

Labeler Agent (labeler/)

• Generates concise 4-5 word session labels
• Analyzes tab titles, URLs, and content patterns
• Used for standalone label generation

Tools (base_agent/tools.py)

• web_search: Serper API integration for real-time info
• get_current_datetime: Context for time-sensitive queries

API Endpoints (main.py)

POST /api/group

• Receives: newTab, existingSessions, currentTabs
• Checks for duplicate tab URLs (fast path)
• Runs multi-agent flow: summarize → match → respond
• Returns: { action, sessionId, updatedLabel, suggestedLabel, reason }
• Comprehensive logging of all ADK events

POST /api/label

• Receives: tabList
• Uses unique session ID per request (no history pollution)
• Returns: { label }

GET /health

• Health check endpoint

Quick Start (ADK Server)

cd adk_server

# Create conda environment
conda create --name session python=3.11
conda activate session

# Install dependencies
python -m pip install -r requirements.txt

# Configure environment
cp .env.example .env
# Add: OPENAI_API_KEY=sk-...
#      SERPER_API_KEY=... (optional, for web search)

# Start server
uvicorn app.main:app --reload
# Server runs on http://localhost:8000

By default the extension points to the hosted backend at https://session-context.onrender.com/api. When running locally, open the options page and set Server API URL to http://localhost:8000/api.

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Development Workflow

1. Start the ADK server:

   cd adk_server
   conda activate session
   uvicorn app.main:app --reload

2. Load the extension:

   • Go to chrome://extensions
   • Enable Developer Mode
   • Click Load unpacked
   • Select the session-context folder

3. Configure (optional):

   • Open the extension options page
   • Keep the default hosted URL https://session-context.onrender.com/api, or switch to http://localhost:8000/api if you’re testing locally
   • Adjust idle threshold, excluded domains as needed

4. Test:

   • Browse various websites (try startup directories, research sites, etc.)
   • Open the popup to see captured sessions
   • Check console logs for decision flow
   • Watch server logs for multi-agent reasoning

5. Monitor:

   • Extension console: chrome://extensions → SessionSwitch → "service worker"
   • Server logs: Watch ADK event JSON in terminal
   • Network tab: Inspect /api/group and /api/label requests

6. Package (for distribution):

   • Zip the session-context directory
   • Exclude adk_server/__pycache__, node_modules, .env files
   • No bundling step needed for the extension

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Customization Tips

Extension

• Constants: Modify utils/constants.js for thresholds, timeouts, and configurations
• Styling: Update popup.css and settings.css for custom themes
• Icons: Replace PNGs or regenerate with icons/generate-icons.html
• Validation: Adjust shouldSkipTab() in background.js for custom filtering

Backend (ADK Server)

• Agent prompts: Fine-tune behavior in:
  • app/summarizer/prompt.py - Tab analysis style
  • app/matcher/prompt.py - Merging logic and label generation
  • app/labeler/prompt.py - Label format and length
  • app/base_agent/agent.py - Coordinator instructions
• Tools: Add new tools in app/base_agent/tools.py (e.g., database lookup, API calls)
• LLM model: Change LiteLlm(model_id="...") in agent files
• Logging: Adjust log levels in app/main.py
• CORS: Modify CORSMiddleware origins for production

Production Hardening

• Extension:
  • Consider moving constants to options page for user configuration
  • Add analytics/telemetry (with user consent)
  • Implement backup/restore for sessions
• Backend:
  • Add authentication (API keys, OAuth)
  • Enable HTTPS with proper certificates
  • Implement rate limiting (per-user, per-IP)
  • Add monitoring (Sentry, DataDog)
  • Use persistent session storage (Redis, PostgreSQL)
  • Deploy with Docker/Kubernetes

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Code Quality & Optimizations

Recent optimizations (Nov 2025):

• ✅ Created constants.js for centralized configuration
• ✅ Reduced codebase by 128 lines (12% smaller)
• ✅ Removed 84 lines of unused code from contentExtractor.js
• ✅ Extracted helper functions: shouldSkipTab(), handleServerDecision(), handleNoActionDecision()
• ✅ Optimized storage operations with Set-based lookups
• ✅ Modernized JavaScript with optional chaining and nullish coalescing
• ✅ Type-safe action constants instead of string literals
• ✅ Comprehensive ADK event logging for debugging
• ✅ Zero linter errors across all files

Performance:

• Fast duplicate detection (O(1) lookups)
• Reduced redundant storage calls
• Optimized filtering with short-circuit evaluation
• Automatic cleanup every 5 minutes

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License

No license is bundled. Add one if you plan to distribute SessionSwitch.

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Acknowledgments

• Built with Google ADK (Agent Development Kit)
• Uses FastAPI for high-performance async backend
• Content extraction powered by Chrome's Scripting API
• Session storage via Chrome's local storage API

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Last Updated: November 2025
Status: ✅ Production-ready with optimized codebase