HTTP+SSE transport

HTTP+SSE transport: The older MCP HTTP transport with a separate SSE endpoint, deprecated since 2025-03-26 and reclassified Deprecated in 2026-07-28. Example: Cloudflare MCP servers return 410 Gone on /sse since 22 Oct 2026. Next in the glossary is MCP Apps: An MCP extension in which a tool points to a ui:// resource the host renders as a sandboxed View.

Definition

The older MCP HTTP transport with a separate SSE endpoint, deprecated since 2025-03-26 and reclassified Deprecated in 2026-07-28.

Example, with source

Cloudflare MCP servers return 410 Gone on /sse since 22 Oct 2026. (developers.cloudflare.com, read 4 November 2026)

Where it appears on this site

• MCP
• Building a remote MCP server

Neighbouring terms

• Elicitation: A way for a server to ask the user, through the client, for more information, now handled through multi round-trip requests.
• MCP Apps: An MCP extension in which a tool points to a ui:// resource the host renders as a sandboxed View.
• MCP client: The connector inside a host application that holds one connection to one MCP server.