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name: ts-google description: Google TypeScript style guide for writing clean, consistent, type-safe code. This skill should be used when writing, reviewing, or refactoring TypeScript code. Triggers on TypeScript files, type annotations, module imports, class design, and code style decisions.

Google TypeScript Best Practices

Comprehensive TypeScript style guide based on Google's internal standards, designed for AI agents and LLMs. Contains 45 rules across 8 categories, prioritized by impact to guide automated refactoring and code generation.

When to Apply

Reference these guidelines when:

• Writing new TypeScript code
• Organizing modules and imports
• Designing type annotations and interfaces
• Creating classes and functions
• Reviewing code for style consistency
• Refactoring existing TypeScript code

Rule Categories by Priority

Quick Reference

1. Module Organization (CRITICAL)

• module-named-exports - Use named exports over default exports
• module-no-mutable-exports - Avoid mutable exports
• module-es6-modules - Use ES6 modules exclusively
• module-no-namespaces - Avoid TypeScript namespaces
• module-import-paths - Use relative paths for project imports
• module-import-type - Use import type for type-only imports
• module-export-api-surface - Minimize exported API surface

2. Type Safety (CRITICAL)

• types-no-any - Never use the any type
• types-prefer-interfaces - Prefer interfaces over type aliases for objects
• types-explicit-structural - Explicitly annotate structural types
• types-nullable-patterns - Handle nullable types correctly
• types-array-syntax - Use consistent array type syntax
• types-no-wrapper-types - Never use wrapper object types
• types-prefer-map-set - Prefer Map and Set over index signatures
• types-no-empty-object - Avoid empty object type

3. Class Design (HIGH)

• class-parameter-properties - Use parameter properties for constructor assignment
• class-readonly-properties - Mark properties readonly when never reassigned
• class-no-private-fields - Use TypeScript private over private fields
• class-no-static-containers - Avoid container classes with only static members
• class-constructor-parens - Always use parentheses in constructor calls
• class-no-prototype-manipulation - Never manipulate prototypes directly

4. Function Patterns (HIGH)

• func-declarations-over-expressions - Prefer function declarations over expressions
• func-arrow-concise-bodies - Use concise arrow function bodies appropriately
• func-avoid-this-rebinding - Avoid rebinding this
• func-rest-parameters - Use rest parameters over arguments
• func-generator-syntax - Use correct generator function syntax
• func-default-parameters - Use default parameters sparingly

5. Control Flow (MEDIUM-HIGH)

• control-always-use-braces - Always use braces for control structures
• control-triple-equals - Always use triple equals
• control-for-of-iteration - Prefer for-of over for-in for arrays
• control-switch-default - Always include default case in switch
• control-no-assignment-in-condition - Avoid assignment in conditional expressions

6. Error Handling (MEDIUM)

• error-throw-errors - Always throw Error instances
• error-catch-unknown - Type catch clause variables as unknown
• error-empty-catch-comments - Document empty catch blocks
• error-avoid-assertions - Avoid type and non-null assertions

7. Naming & Style (MEDIUM)

• naming-identifier-styles - Use correct identifier naming styles
• naming-descriptive-names - Use descriptive names
• naming-no-decorative-underscores - Avoid decorative underscores
• naming-no-interface-prefix - No I prefix for interfaces
• naming-constants - Use CONSTANT_CASE for true constants

8. Literals & Coercion (LOW-MEDIUM)

• literal-single-quotes - Use single quotes for strings
• literal-number-formats - Use correct number literal formats
• literal-explicit-coercion - Use explicit type coercion
• literal-array-constructor - Avoid Array constructor

How to Use

Read individual reference files for detailed explanations and code examples:

• Section definitions - Category structure and impact levels
• Rule template - Template for adding new rules

Reference Files