Does time_server Support MCP Protocol (STDIO)? Is HTTP-Only Expected?

[michaelbev]

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Question Category

• Protocol Specification
• SDK Usage
• Server Implementation
• General Implementation
• Documentation
• Other

Your Question

Hi all,

I’m working with the modelcontextprotocol/servers project and using Cursor as my development environment. I noticed that most MCP servers like the Go-based toolbox server can be started in either STDIO (MCP protocol) or HTTP mode, depending on the flags you use.

However, when I use the Python-based time_server (from src/time), it appears to only support HTTP mode (serving a FastAPI/OpenAPI interface). I don’t see any option to start it in STDIO mode or to have it speak the MCP protocol over STDIO, as Cursor expects for some integrations.

My questions for the community:

• Is it expected that time_server only supports HTTP and not STDIO/MCP protocol?
• Has anyone added or is anyone working on MCP protocol (STDIO) support for time_server?
• Is it considered strange or inconsistent that time_server does not support STDIO, given that other MCP servers do?
• Are there recommended workarounds for using time_server with tools/environments (like Cursor) that expect STDIO/MCP support?

Additional Context
I noticed that Cursor is able to use time_server even though it only exposes an HTTP API and does not support STDIO/MCP protocol. It seems that Cursor is smart enough to use HTTP for servers that do not specify --stdio in .cursor/mcp.json. If you start a server without --stdio, Cursor will use HTTP if the server exposes an HTTP API. This works well for time_server, but I want to confirm if this is the recommended approach for integrating HTTP-only MCP servers with Cursor, and if there are any best practices or caveats I should be aware of.

Any insights or pointers to documentation would be greatly appreciated!

Thanks in advance!