SSE tester

Test SSE endpoints — with custom headers, where EventSource can’t.

Realtime tab → SSE · 7-day free trial · Premium $9.99 / yr

What it does

Server-Sent Events is the lightweight unidirectional alternative to WebSocket. AI streaming APIs (OpenAI, Anthropic) use it. The native EventSource API doesn’t allow custom headers — which is a problem when your API needs Authorization.

VibeGear uses fetch + ReadableStream instead, so the full HTTP header set works. We parse the SSE wire format ourselves and reconnect per spec (using Last-Event-ID and the server’s retry: hint).

How to use it

1. 1Realtime tab → SSE.
2. 2Paste your https:// SSE endpoint.
3. 3Add headers if your API needs them.
4. 4Connect — events stream into the timeline.

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