Python MCP SDK 2.x Renames FastMCP to MCPServer, Requires Migration Steps

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The MCP Python SDK 2.x introduced a breaking change by renaming FastMCP to MCPServer, causing ModuleNotFoundError for projects that had no version pin on the mcp package. Key changes include the replacement of httpx with a fork called httpx2, sync handlers now running on worker threads instead of the event loop, and several API renames such as McpError becoming MCPError. Projects with an unpinned mcp dependency in requirements.txt will silently upgrade to 2.x on a fresh install, triggering these errors. Developers can either migrate their code following the official SDK migration guide or pin their dependency to mcp version below 2.0 to maintain compatibility.

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