Core Rules for Cursor AI Interactions

Project Context

This is a TypeScript-based URL routing library that supports browser, server, and in-memory routing with observable patterns.

Code Style and Standards

• Use TypeScript with strict mode enabled
• Follow ESM module system
• Maintain consistent formatting:
  • 2-space indentation
  • 100 character line length
  • Single quotes for strings
  • Trailing commas in objects and arrays
  • No semicolons at the end of statements
  • Arrow function parentheses only when needed

File Organization

• Source files: src/ directory
• Test files: Co-located with source files using .test.ts suffix
• File naming: PascalCase for source files, matching pattern ^[A-Z][a-zA-Z0-9]*\.ts$

Testing Requirements

• Use Vitest for testing
• Maintain minimum 80% test coverage
• Write unit tests for all new functionality
• Include integration tests for routing scenarios

Code Quality Rules

• No console.log statements in production code
• No debugger statements
• No unused variables
• Prefer const over let
• No var declarations
• Strict null checks
• No implicit any types

Import Organization

• Group imports by type:
  1. Node.js built-in modules
  2. External dependencies
  3. Internal modules
• Sort imports alphabetically within groups
• Use named imports when possible

Documentation

• Include JSDoc comments for public APIs
• Document complex routing patterns
• Keep README.md up to date with new features
• Include examples for common use cases

Error Handling

• Use TypeScript's type system to prevent runtime errors
• Implement proper error boundaries for routing failures
• Provide meaningful error messages for debugging

Performance Considerations

• Minimize unnecessary re-renders in routing components
• Optimize route matching algorithms
• Consider memory usage in long-running applications

Security Guidelines

• Validate all URL inputs
• Sanitize route parameters
• Prevent XSS attacks through route parameters
• Follow security best practices for URL manipulation

Accessibility

• Ensure routing changes are announced to screen readers
• Maintain focus management during navigation
• Support keyboard navigation

Version Control

• Write clear commit messages
• Keep commits focused and atomic
• Follow semantic versioning for releases

Tool Usage

• Use edit_file for code modifications
• Use codebase_search for finding relevant code
• Use read_file for understanding existing code
• Use run_terminal_cmd for necessary shell operations
• Use grep_search for finding specific patterns
• Use list_dir for exploring project structure
• Use delete_file for removing files

Response Format

• Use markdown for all responses
• Include code blocks with appropriate language tags
• Provide clear explanations for code changes
• Include relevant context in explanations