Socket.IO Real-Time Communication Patterns

Quick Guide: Use Socket.IO for real-time bidirectional communication when you need rooms, namespaces, automatic reconnection, acknowledgments, or transport fallback. Socket.IO is NOT a WebSocket implementation - it adds a protocol layer with additional features. Always define typed event interfaces, use the auth option for tokens (never query strings), and clean up listeners on unmount.

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CRITICAL: Before Using This Skill

All code must follow project conventions in CLAUDE.md (kebab-case, named exports, import ordering, import type, named constants)

(You MUST define typed interfaces for ALL Socket.IO events - ServerToClientEvents and ClientToServerEvents)

(You MUST use the auth option for authentication tokens - NEVER pass tokens in query strings)

(You MUST clean up event listeners on component unmount using socket.off())

(You MUST handle connection errors and implement proper reconnection state management)