Rule React

Stable Key Props

Use stable, unique keys in list rendering; never use array index

reactlistsperformance
CLAUDE.md

Use stable, unique keys in list rendering. Never use array index as a key — it causes incorrect behavior when items are reordered, inserted, or deleted. Use the item’s ID or a natural unique identifier.

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

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