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uvicorn got eagerly imported via sse-starlette #1770
Description
Initial Checks
- I confirm that I'm using the latest version of MCP Python SDK
- I confirm that I searched for my issue in https://github.com/modelcontextprotocol/python-sdk/issues before opening this issue
Description
I noticed that you intend to lazy-import uvicorn because it's only used for HTTP/SSE transports. However, I found that it's still being imported immediately, as sse-starlette imports it eagerly, and sse-starlette is imported here:
Example Code
import sys, mcp
assert "uvicorn" in sys.modulesPython & MCP Python SDK
1.23.3
Activity
CNSeniorious000 commentedon Dec 11, 2025
Sad to see #1771 only trims ~50 ms—even though
import sse_starlettetakes 400 ms, it turns outuvicornitself is pretty light. Feel free to close if you're fine leaving things as-is.[-]`uvicorn` got eagerly imported because of `sse-starlette`[/-][+]`uvicorn` got eagerly imported via `sse-starlette`[/+]maxisbey commentedon Dec 11, 2025
Yea will leave as is for now :)