Rules Catalog

30 rules automatically applied by file path

30

Rules

156

Patterns

What is a Rule?

Rules are conventions applied automatically:

• Apply by path: Activated according to the file path
• Code conventions: TypeScript, React, Flutter, etc.
• Best practices: Security, tests, API
• Transparency: Always visible in suggestions

List of rules

Rule	Description	Paths
accessibility	IMPORTANT: Every image must have an alt attribute....	**/*.tsx, **/*.jsx...
api	// Error { "success": false, "error": { "code": "V...	**/api/**, **/routes/**...
astro	Astro renders zero JS by default. Components a...	**/*.astro, **/astro.config.*...
base-maintenance	Any addition, removal or rename in .claude/ sile...	.claude/skills/**, .claude/agents/**...
csharp	// 2. Private readonly fields private readonly IUs...	**/*.cs, **/*.csproj...
deploy-safety	Every deployment must be validated before executio...	**/docker-compose*.yml, **/docker-compose*.yaml...
design-style	The project's design direction is defined in CLAUD...	**/*.tsx, **/*.jsx...
flutter	// State abstract class AuthState {} class AuthIni...	**/*.dart, **/lib/**...
git	[optional body - details on the "what" and "why"]	-
go	// Custom errors var ErrUserNotFound = errors.New(...	**/*.go, **/go.mod...
java	// 2. Static fields private static final Logger lo...	**/*.java, **/pom.xml...
lsp	LSP available via ENABLE_LSP_TOOL=1 or LSP plugi...	**/*.ts, **/*.tsx...
migration-safety	Major framework or dependency migrations are risky...	**/package.json, **/tsconfig.json...
nextjs	Next.js Rules	**/next.config.*, **/app/**...
performance	IMPORTANT: LCP < 2.5s - Optimize above-the-fold im...	**/*.tsx, **/*.jsx...
php	declare(strict_types=1);	**/*.php, **/composer.json
python	import requests from pydantic import BaseModel	**/*.py, **/requirements*.txt...
react	export function MyComponent({ title, onAction }: P...	**/*.tsx, **/components/**...
research	Before implementing a custom solution, check wheth...	**/*.ts, **/*.tsx...
ruby	users.each do	user
rust	// 2. Constants const MAX_CONNECTIONS: usize = 100...	**/*.rs, **/Cargo.toml
security	3 attack vectors identified (Feb. 2026) when cloni...	**/auth/**, **/api/**...
service-worker	The SW must NEVER cache `request.mode === "navigat...	**/sw.js, **/service-worker*...
svelte	Svelte 5+ uses runes: $state, $derived, `$...	**/*.svelte, **/*.svelte.ts...
tdd-enforcement	IMPORTANT: When the user asks to implement, add, c...	**/*.ts, **/*.tsx...
testing	// Act - Execute the action const result = functio...	**/*.test.ts, **/*.test.tsx...
typescript	TypeScript Rules	**/*.ts, **/*.tsx...
verification	Any implementation must be verified BEFORE being c...	**/*.ts, **/*.tsx...
vue	const count = ref(0) const double = computed(() =>...	**/*.vue, **/composables/**...
workflow	Before starting work on an existing project:	-

Categories

Languages

• csharp
• go
• java
• php
• python
• ruby
• rust
• typescript

Frameworks

• flutter
• react

Practices

• api
• git
• security
• testing
• workflow

How to add a custom rule

Create a file .claude/rules/my-rule.md:

---
paths:
  - "**/my-folder/**"
  - "**/*.custom"
---

# My custom rules

- Rule 1
- Rule 2

---

See also

• Architecture - Understand the components
• Commands - Manual commands
• Skills - Auto-triggered skills