Rule TypeScript

Readonly Properties

Mark object properties as readonly when they shouldn't be mutated

typescriptimmutabilitysafety
CLAUDE.md

Mark object properties as readonly when they shouldn’t be mutated. Use Readonly<T>, ReadonlyArray<T>, and as const to enforce immutability at the type level.

Copy this block into your CLAUDE.md or agent config file to enforce it in your workflow.

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