MCP Python SDK

Official Python SDK for the Model Context Protocol (MCP), maintained by Anthropic. Used to build MCP servers (exposing tools, resources, prompts to LLMs) and MCP clients. Two important ecosystem distinctions: (1) mcp package bundles FastMCP 1.0 via mcp.server.fastmcp; (2) standalone 'fastmcp' package on PyPI is a separate, more feature-rich framework that diverged from the bundled version. v2 of the mcp package is in pre-alpha on main branch — v1.x is stable.