GitHub repository documents 16 prompt injection techniques and defense strategies for public AI chats

A developer built a custom AI chat on their website as an experiment and encountered multiple security challenges when real users attempted to break it. The experience prompted the creation of a comprehensive security guide available on GitHub.
Security challenges encountered
Users attempted various attacks including:
- Prompt injection
- Roleplay attacks
- Multilingual tricks
- Base64 encoded payloads
Defense strategies implemented
The developer documented a defense-in-depth approach covering:
- Input sanitization
- Rate limiting
- Zero-trust system prompt design
- Output controls
- Cost caps
GitHub repository contents
The repository includes:
- A breakdown of 16 prompt injection techniques
- A Claude code skill that automatically tests all 16 techniques against your chatbot
- Full defense implementation details
The developer notes that users tried things they "never would have thought to test" and that the guide is intended to be useful for anyone implementing similar public AI chat systems.
📖 Read the full source: r/ClaudeAI
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