Streamable HTTP is a new transmission method introduced in MCP (Model Context Protocol) to improve scalability, flexibility, and compatibility compared to the older HTTP SSE transport. It allows clients and servers to communicate using standard HTTP POST and GET requests, making it easier to integrate with cloud platforms, CDNs, and microservice architectures while supporting features like stateless operation and optional SSE streams for real-time updates.
Currently, adoption of Streamable HTTP by end-user-facing clients like Cursor or Windsurf seems limited, as most SDKs and tools are still transitioning to support this protocol. However, some progress has been made with the http4k MCP SDK and desktop client, which now offer compatibility with the latest MCP specifications.