Rules for AI

Using rules in Cursor you can control the behavior of the underlying model. You can think of it as instructions and/or a system prompt for LLMs.

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Project Rules (recommended)

Project rules offer a powerful and flexible system with path specific configurations. Project rules are stored in the .cursor/rules directory and provide granular control over AI behavior in different parts of your project.

Here’s how they work

• Semantic Descriptions: Each rule can include a description of when it should be applied
• File Pattern Matching: Use glob patterns to specify which files/folders the rule applies to
• Automatic Attachment: Rules can be automatically included when matching files are referenced
• Reference files: Use @file in your project rules to include them as context when the rule is applied.

You can create a new rule using the command palette with Cmd + Shift + P > New Cursor Rule. By using project rules you also get the benefit of version control since it’s just a file

Example use cases:

• Framework-specific rules for certain file types (e.g., SolidJS preferences for .tsx files)
• Special handling for auto-generated files (e.g., .proto files)
• Custom UI development patterns
• Code style and architecture preferences for specific folders

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Global Rules

Global rules can be added by modifying the Rules for AI section under Cursor Settings > General > Rules for AI. This is useful if you want to specify rules that should always be included in every project like output language, length of responses etc.

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.cursorrules

For backward compatibility, you can still use a .cursorrules file in the root of your project. We will eventually remove .cursorrules in the future, so we recommend migrating to the new Project Rules system for better flexibility and control.