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+# Copilot Instructions for AI Book Reader
+
+## Project Overview
+This is an AI-assisted book reader application designed to enhance the reading experience through artificial intelligence features.
+
+## Development Guidelines
+
+### Code Style and Standards
+- Write clean, readable, and well-documented code
+- Use meaningful variable and function names
+- Follow consistent formatting and indentation
+- Add comments for complex logic or algorithms
+
+### Project Context
+- This is an AI-powered book reading application
+- Focus on user experience and accessibility
+- Consider performance implications for file processing and AI operations
+- Maintain compatibility across different file formats and devices
+
+### Architecture Principles
+- Keep components modular and reusable
+- Separate concerns between UI, business logic, and AI processing
+- Use appropriate design patterns for scalability
+- Implement proper error handling and logging
+
+### AI Integration Best Practices
+- Handle AI API calls gracefully with proper error handling
+- Implement fallback mechanisms when AI services are unavailable
+- Consider rate limiting and cost optimization for AI operations
+- Support user-provided OpenAI API keys (BYOK - Bring Your Own Key) for enhanced privacy and cost control
+- Ensure user privacy and data security when processing book content
+- Validate and secure API key storage using environment variables or secure configuration
+
+### Testing Guidelines
+- Write unit tests for core functionality
+- Test AI integration components thoroughly
+- Include edge cases and error scenarios
+- Maintain good test coverage for critical paths
+
+### Documentation Standards
+- Update README.md with setup and usage instructions
+- Document API endpoints and data models
+- Include examples for complex features
+- Keep documentation current with code changes
+
+### Security Considerations
+- Sanitize user inputs, especially file uploads
+- Implement proper authentication and authorization if needed
+- Secure API keys and sensitive configuration using environment variables or encrypted storage
+- Never log or expose user-provided API keys in plain text
+- Provide clear warnings about API key security when users input their own keys
+- Follow security best practices for file handling
+
+## Specific Guidance for This Repository
+
+### File Processing
+- Support multiple book formats (PDF, EPUB, TXT, DOCX, etc.)
+- Implement efficient text extraction and processing
+- Handle large files gracefully with streaming or chunking
+
+### AI Features
+- Implement smart bookmarking and note-taking
+- Provide reading comprehension assistance
+- Support text summarization and key insights
+- Enable semantic search within books
+- Allow users to configure their own OpenAI API keys for personalized AI services
+- Provide clear UI for API key management with proper security warnings
+
+### User Interface
+- Design for readability and eye comfort
+- Support different themes (light/dark mode)
+- Implement responsive design for various screen sizes
+- Ensure accessibility compliance (WCAG guidelines)
+
+### Performance
+- Optimize for fast loading and smooth scrolling
+- Implement efficient caching strategies
+- Minimize memory usage for large documents
+- Use lazy loading for content-heavy pages
+
+When contributing to this project, always consider the end-user experience and how features will enhance the reading journey while maintaining performance and security standards.
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