Why Your AI UX Is Broken (and It's Not the Model's Fault) — Mike Christensen, Ably

SSE ties a response stream to a single connection. The user refreshes the page, walks out of WiFi range, or opens a second tab and the in-progress response is gone. Abort and resume are mutually exclusive for the same reason: the only signal a client can send over a one-way pipe is closing it, so the agent cannot tell the difference between a cancel and a disconnect. Vercel's AI SDK documents this explicitly. Mike Christensen from Ably makes the case for treating the session itself as a durable shared resource, decoupled from any individual connection, device, or agent instance. Clients subscribe to the session rather than to a request, so reconnects resume automatically, any tab or device has full visibility of live activity, and concurrent agents write independently without routing everything through an orchestrator. The demo shows all of this: multi-tab sync, a forced network disconnect that self-recovers, two agents running in parallel, and a handoff to a human support agent who joins the session mid-conversation with the full interaction history already visible. Speaker info: - https://x.com/christensencode - https://www.linkedin.com/in/mikescottchristensen/