Streamable HTTP
Streamable HTTP - MCP's HTTP transport, introduced in the 2025-03-26 revision as the replacement for the original HTTP+SSE transport. A single endpoint accepts JSON-RPC POST requests; since 2026-07-28, requests must carry the Mcp-Method and Mcp-Name headers for header-based routing, and the legacy HTTP+SSE transport is formally deprecated.
Streamable HTTP is the transport that made remote MCP servers practical: one HTTP endpoint accepting JSON-RPC POST bodies, with optional streaming responses. It replaced the original HTTP+SSE transport in the 2025-03-26 revision. The 2026-07-28 revision tightened it for infrastructure: requests must carry Mcp-Method and Mcp-Name headers so gateways, rate limiters, and WAFs can route and meter without parsing JSON bodies, and SSE stream resumability was removed along with protocol-level sessions. The legacy HTTP+SSE transport is now formally deprecated with a twelve-month minimum removal window.
Where to see Streamable HTTP in the catalog
| Entity | Type | Note |
|---|---|---|
| Vercel MCP | server | Remote endpoint speaking Streamable HTTP. |
| GitHub MCP Server | server | Hosted remote endpoint speaking Streamable HTTP. |
Related concepts
Sources and verification
Last verified · confidence 1.00.
- Official 2025-03-26 changelog - Streamable HTTP transport replaces the previous HTTP+SSE transport (PR #206) - accessed
- Official 2026-07-28 changelog - Mcp-Method and Mcp-Name headers required on Streamable HTTP POST requests (SEP-2243); HTTP+SSE reclassified as Deprecated under the feature lifecycle policy (SEP-2596) - accessed