AI chat stream resumption: when Redis is enough, and when you need durable sessions

What this post added

This post details the limitations of Redis-based stream resumption for AI chat applications, particularly concerning write amplification, cancellation ambiguity, multi-device support, and enterprise network delivery. It contrasts this with the benefits of a durable session layer provided by Ably AI Transport, which handles stream resumption, multi-device synchronization, and security as inherent properties of the transport. The post also provides a code snippet demonstrating the integration of Ably AI Transport with Vercel's useChat hook.