How to make SSE token streams resumable, cancellable, and multi-device
2 days ago
- #AI Agents
- #Token Streaming
- #Server-Sent Events
- Agents have evolved from synchronous interactions to background operations, breaking traditional transport methods.
- Advanced chatbot features include resumable streams, cancellations, and multi-device support, achievable but not necessarily easy with Server-Sent Events (SSE).
- LLM responses consist of tokens with metadata; storing each token for resumability leads to inefficient database writes and cleanup.
- Resumable streams require storing tokens in a shared database due to stateless server replicas, increasing write amplification.
- Cancellations require a separate endpoint and shared store to signal abort, complicating dropped connection handling.
- Multi-device support involves sharing token streams and real-time updates, often necessitating polling or long-polling solutions.
- SSE over HTTP is criticized as inefficient for streaming LLM tokens; pub/sub patterns offer better decoupling and automation for AI applications.