MCP Python SDK 发布: v2.0.0

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# MCP Python SDK v2 Stable Release This is v2.0.0, the stable v2 release of the MCP Python SDK. It supports the 2026-07-28 revision of the Model Context Protocol and serves every earlier revision from the same server. `pip install mcp` now installs 2.x. ```bash pip install "mcp[cli]" # or uv add "mcp[cli]" ``` ### Documentation Rewrite The [documentation](https://py.sdk.modelcontextprotocol.io/) has the full tutorial and API reference. Coming from v1? [What's new in v2](https://py.sdk.modelcontextprotocol.io/whats-new/) is the tour of what changed and why, and the [migration guide](https://py.sdk.modelcontextprotocol.io/migration/) lists every breaking change with before-and-after code. ### V1 Maintenance mode **v1.x is in maintenance mode and will only receive security fixes from now on** The 1.x line lives on the [`v1.x` branch](https://github.com/modelcontextprotocol/python-sdk/tree/v1.x), continues to receive critical bug fixes and security patches, and is documented at https://py.sdk.modelcontextprotocol.io/v1/. If your project is not ready to migrate, keep a `<2` upper bound on your requirement (for example `mcp>=1.28,<2`). ## Highlights ### One SDK, both protocol eras v2 speaks the 2026-07-28 revision (stateless requests with no handshake, `server/discover`, `subscriptions/listen`, multi-round-trip requests) and still serves every 2025-era client from the same `MCPServer`, over Streamable HTTP and stdio, with nothing to configure. `Client(target)` negotiates the version automatically. ### `FastMCP` is now `MCPServer`, and there is a first-class `Client` The decorator API is unchanged; the low-level `Server` is rebuilt around a shared dispatcher engine, and one `Client` object replaces v1's transport-plus-`ClientSession`-plus-`initialize()` layering. It connects t