Inspiration
As internet users, we’ve seen countless stories of elderly people where one suspicious link has led to a drained bank account. From fake refund emails to urgent "family in trouble" WhatsApp messages, online scams are everywhere. Yet, most users lack tools that warn them before it’s too late.
We asked ourselves:
“What if we could build an AI that warns you before you get scammed — and teaches you how to avoid it in the future?”
That question led us to build Scamurai — a lightweight Chrome extension that defends users from scams and trains them to recognize them independently.
What it does
Scamurai is a real-time scam detection and training tool, built into a simple Chrome extension. It:
- Scans emails and messages in real time on platforms like Gmail and WhatsApp Web
- Assigns a threat level (Low, Medium, High) using Gemini-powered analysis
- Explains the red flags in plain English — like urgency, impersonation, or fake links
- Trains users in a simulated “Scamurai Dojo” — where they practice identifying scams in realistic environments
- Works without storing any personal data, respecting user privacy
Scamurai bridges the gap between passive tools and user awareness — combining detection and education in one tool.
How we built it
Scamurai combines two core systems: a browser extension and a React training app.
Browser Extension
- Frontend: JavaScript, HTML, and CSS for the floating UI and popup interface
- Content Scripts: Extracts visible text from Gmail and WhatsApp Web
- Backend: Python Flask API handles routing and analysis
- Gemini API: Used to analyze messages and return:
- Scam classification
- Risk level
- Explanation and red flags
Training Dojo
- React frontend with styled-components for modular styling
- Simulated email and chat environments with custom-built Gmail/WhatsApp-like components
- Context-based state management for progress tracking
- Feedback system with correct/incorrect explanation overlays
- Custom loaders, animated transitions, and UI polish for accessibility
The AI integration was prompt-engineered to emphasize scam traits and produce non-technical explanations.
We focused on lightweight performance, seamless UX, and trustworthy AI outputs.
And the best part is, it speaks to you like a samurai!
Challenges we ran into
- Precision in scam detection: Crafting Gemini prompts that balance false positives vs. user safety
- Context awareness: Messages are short and nuanced — teaching the AI to detect intent required iteration
- Dojo realism: Simulating Gmail and WhatsApp layouts in a way that feels familiar and functional
- Performance: Making sure scans return results quickly without interrupting user experience
- UX balance: Designing a UI that warns users clearly — without being intrusive or fear-driven
Accomplishments that we're proud of
- Built a fully working scam detection pipeline with Gemini-generated reasoning and custom threat scoring
- Developed a complete training simulator to improve long-term scam awareness
- Created a system that works across two major platforms — Gmail and WhatsApp Web
- Achieved a clean, non-invasive UI that’s friendly to non-technical users
- Ensured privacy-first design — no message data is stored permanently
What we learned
This project taught us:
- The importance of prompt engineering when working with general-purpose LLMs
- How to turn natural language cues into structured scam detection
- That protecting users isn’t just about technology — it’s about communicating clearly
- How to balance AI automation with user control, especially for older users
- That education and prevention go hand-in-hand when it comes to cybersecurity
Most importantly, we learned that real protection requires a layered approach — proactive detection + user empowerment.
What's next for Scamurai
- Mobile browser support for scam detection in mobile apps
- User-adaptive training mode — adjusting difficulty based on user progress
- Real-time alerts + scam trend dashboard
- Third-party integration support (e.g., Facebook Messenger, SMS, Telegram)
Our goal is to make Scamurai the go-to tool for everyday digital defense — because everyone deserves to feel safe online.
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