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Align with spec #3002: optional clientInfo, serverInfo in result _meta (#3143)

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Max 2026-07-23 12:00:36 +01:00 • committed by GitHub
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4
docs/client/index.md
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@ -30,7 +30,7 @@ Everything else on this page is identical across all three. Headers, subprocesse
Four read-only properties, populated the moment you enter the block:
* `client.server_info`: the server's identity. `server_info.name` here is `"Bookshop"`, `server_info.version` is whatever the server reports.
* `client.server_info`: the server's identity, or `None` for a 2026-era server that does not report one (python-sdk servers do by default). `server_info.name` here is `"Bookshop"`, `server_info.version` is whatever the server reports.
* `client.server_capabilities`: what the server can do (`tools`, `resources`, `prompts`, `completions`, ...). A capability the server doesn't have is `None`.
* `client.protocol_version`: the protocol version the two sides agreed on. Here it is `"2026-07-28"`.
* `client.instructions`: the server's `instructions=` string, or `None` if it didn't set one.
@ -202,7 +202,7 @@ There is one constructor flag built for that: `Client(mcp, raise_exceptions=True
## Recap
* `Client(x)` connects in-memory to a server object, over Streamable HTTP to a URL string, and over anything else via a transport.
* `async with` is the whole lifecycle. Inside it, `server_info`, `server_capabilities`, `protocol_version` and `instructions` are already populated.
* `async with` is the whole lifecycle. Inside it, `server_capabilities` and `protocol_version` are already populated; `server_info` and `instructions` are too when the server provides them.
* `list_tools()` gives you each tool's `name`, `title`, `description` and `input_schema`.
* `call_tool()` returns `content` for the model, `structured_content` for your code, and `is_error`. A raising tool is a result, not an exception.
* `content` is a union of block types; narrow with `isinstance` before reading.

2
docs/client/session-groups.md
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@ -64,7 +64,7 @@ Run it again. `print(sorted(group.tools))` now shows both:
`connect_to_server` returns the `ClientSession` it opened. Keep it if you ever want that server gone: `await group.disconnect_from_server(session)` removes its tools, resources, and prompts from the group.
If you already hold a connected `ClientSession` (`Client.session` is one), hand it to `await group.connect_with_session(server_info, session)` instead of opening a new transport. It aggregates the same way. The group never closes a session it didn't open.
If you already hold a connected `ClientSession` (`Client.session` is one), hand it to `await group.connect_with_session(server_info, session)` instead of opening a new transport. It aggregates the same way. The group never closes a session it didn't open. `server_info` names the server for component prefixes; on a 2026-era connection `client.server_info` can be `None` (identity is optional), so pass your own `Implementation(name=..., version=...)` in that case.
## The classic handshake