All specs
HTML LS §SSEWHATWGShould KnowProduct

Server-Sent Events

Real-time·Web Hypertext Application Technology Working Group
WHY YOU NEED THIS

The go-to protocol for server-push without WebSocket complexity. Used for AI/LLM streaming responses, live notifications, and real-time dashboards over plain HTTP.

What It Defines

Defines the EventSource API and the text/event-stream wire format for one-way server-to-client push over HTTP. Simpler than WebSocket for unidirectional push: notifications, live feeds, streaming AI responses.

Canonical (Normative)

Convenient (Practical)

sserealtimepushstreaminghttp
Standards Body
Web Hypertext Application Technology Working Group

Maintains the living standards for the web platform: HTML, DOM, Fetch, URL, Streams, and more. These are continuously updated living documents, not versioned snapshots.

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