What is Streamable HTTP?

Streamable HTTP is the transport the Model Context Protocol uses for remote servers reached over the network. The client sends requests to a single HTTP endpoint and the server can stream responses back, which supports both quick request-response calls and longer-running, incremental results. It replaced the earlier HTTP plus Server-Sent Events (SSE) approach, though some servers still expose a separate /sse endpoint as a fallback for older clients. Because the server lives at a URL rather than as a local process, Streamable HTTP is what makes hosted, always-on, team-shared servers possible, and it is typically paired with OAuth so each user authorizes their own access without putting secrets in a config file. When you see an MCP setup that is just a URL, like a hosted documentation, issue-tracker, or memory server, it is almost always speaking Streamable HTTP.