Configuring Rules & Docs

🎯 Foundation First: This guide assumes you've completed Project Setup and understand Cursor's basic interface. Rules configuration is an advanced topic for optimizing AI behavior.

Critical Importance

Cursor Rules are absolutely essential before rolling out AI-assisted development to production teams. Without proper rules, AI suggestions can be inconsistent, violate coding standards, or introduce subtle bugs that are difficult to catch in code reviews.

🎯 What are Cursor Rules?

Cursor Rules are configuration files that:

• Define coding standards and conventions
• Provide domain-specific context to AI
• Ensure consistent code quality across teams
• Integrate with project-specific patterns
• Enforce security and compliance requirements

🚀 Getting Started: Learn about the basic Rules and Memories interface in Introduction to Cursor AI

📚 Official Documentation

Essential Reading: https://docs.cursor.com/en/context/rules

Key sections to review:

• Basic Rules Setup
• Advanced Configuration
• Team Collaboration

🎯 Cursor Rules System

According to the official Cursor documentation, Cursor uses a Project Rules system with .cursor/rules/ directory containing multiple .mdc files.

Modern Project Rules Benefits

• Better Organization: Separate rules by domain/purpose
• Improved Scope: Rules can target specific file patterns with globs
• Rule Types: Always, Auto Attached, Agent Requested, or Manual
• Version Control: Full integration with git and team workflows
• Nested Rules: Organize rules in subdirectories for different project areas

Note: The legacy .cursorrules file is still supported but the modern .cursor/rules/ system is recommended for new projects.

📝 How Rules Work

Based on the official Cursor documentation, rules provide system-level instructions to Agent and Inline Edit:

• Persistent Context: Rules provide consistent guidance across AI interactions
• Prompt-Level Instructions: Rule contents are included at the start of model context
• Version Controlled: Rules are stored as files and can be managed with git
• Scoped Application: Rules can target specific files, directories, or project areas

Rule Types

Rule Type	Behavior	When to Use
Always	Always included in model context	Core project standards
Auto Attached	Included when matching files are referenced	File-specific patterns
Agent Requested	AI decides whether to include	Specialized knowledge
Manual	Only when explicitly mentioned with @ruleName	On-demand guidance

🗂️ Rule Anatomy (.mdc Format)

Rules use MDC (Markdown with metadata) format:

---
description: Brief description of the rule's purpose
globs: ["*.py", "*.cs"]        # File patterns (optional)
alwaysApply: true              # Boolean (optional)
---

# Rule Content
Your rule instructions in markdown format.

## Referenced Files
@template-file.py              # Include additional context

Key Properties

• description: Required for Agent Requested rules, helps AI understand purpose
• globs: File patterns using standard glob syntax for auto-attachment
• alwaysApply: Set to true for rules that should always be active
• Referenced Files: Use @filename to include additional context files

🏗️ Basic BIM Rules Setup

Essential Rules Structure:

project/
├── .cursor/rules/
│   ├── bim-standards.mdc      # Always applied core standards
│   ├── revit-patterns.mdc     # Auto-attached for Revit files
│   └── documentation.mdc     # Manual rule for docs generation

Example: Core Standards Rule

---
description: Basic BIM development standards
alwaysApply: true
---

# BIM Development Standards

## Code Quality
- Include comprehensive error handling
- Use descriptive names for BIM elements
- Add docstrings for all public functions
- Follow language-specific conventions (PEP 8 for Python)

## BIM-Specific Guidelines
- Always use transactions for Revit model modifications
- Validate element existence before processing
- Handle large datasets efficiently
- Include progress reporting for long operations

🔧 Creating Rules

Using Cursor Interface

Create rules through Cursor's interface:

1. New Rule Command: Use Ctrl+Shift+P → "New Cursor Rule"
2. Settings Panel: Go to Cursor Settings > Rules
3. Generate from Chat: Use /Generate Cursor Rules command in chat

Rule Best Practices

Based on the official Cursor documentation:

• Keep rules focused: Each rule should have a specific purpose
• Under 500 lines: Split large rules into multiple composable rules
• Provide examples: Include concrete code examples in rules
• Clear descriptions: Write descriptions like internal documentation
• Reference files: Use @filename to include additional context

Nested Rules

Organize rules in subdirectories for different project areas:

project/
├── .cursor/rules/           # Project-wide rules
├── backend/
│   └── .cursor/rules/      # Backend-specific rules
└── frontend/
    └── .cursor/rules/      # Frontend-specific rules

Team Collaboration Rules

Code Review Requirements

• All AI-generated code must be reviewed by senior developer
• Focus review on business logic and Revit API usage
• Verify error handling and edge cases
• Check performance implications for large models

Version Control

• Use semantic versioning (1.0.0)
• Include clear commit messages
• Tag releases with release notes
• Maintain changelog

Deployment Standards

• Test with multiple Revit versions
• Validate with sample models
• Document any breaking changes
• Provide migration guides

🎯 User Rules (Global Settings)

Configure global rules in Cursor Settings > Rules that apply to all projects:

# Global Development Standards

## Communication Style
- Provide concise, actionable responses  
- Include code examples with explanations
- Focus on domain-specific solutions

## Code Quality Standards
- Always include proper error handling
- Use descriptive variable and function names
- Add inline documentation for complex operations
- Follow language-specific conventions (PEP 8 for Python, Microsoft for C#)

📋 Rule Management Tips

FAQ from Official Documentation

Why isn't my rule being applied?

• Check rule type and file pattern matching
• Ensure description is provided for Agent Requested rules
• Verify globs patterns match your files

Can rules reference other files?

• Yes, use @filename.ts to include additional context
• Referenced files are included when the rule triggers

Do rules affect all Cursor features?

• No, rules only apply to Agent and Inline Edit features
• Tab completion and other features are not affected

---

🚀 Next Steps

Start with basic rules and gradually expand based on your team's needs:

1. Project Setup - Set up your basic rules structure
2. Hands-On Examples - See advanced DCMvn-specific rules and patterns in action
3. Chat Mode - Learn how rules integrate with conversational AI development