load_mcp_server_info

Parameters

Name	Type	Description
`session`*	`ClientSession \| None`	An MCP client session that has not been initialized yet. If provided, this function calls `initialize()` on it. If `None`, a `connection` must be provided and a temporary session will be created automatically.
`connection`	`Connection \| None`	Default:`None` Connection config to create a new session if `session` is `None`.
`callbacks`	`Callbacks \| None`	Default:`None` Optional `Callbacks` for handling notifications and events. Only applied to sessions created from `connection`; ignored when `session` is provided, since the caller owns that session's callbacks.
`server_name`	`str \| None`	Default:`None`

Load server info from the MCP initialize handshake.

Returns the full InitializeResult from the MCP protocol, which includes server instructions, capabilities, implementation details, and protocol version.

Note

Unlike load_mcp_tools, load_mcp_prompt and load_mcp_resources, which expect an already-initialized session, this function performs the initialize() handshake itself and therefore requires a session that has not been initialized yet. MultiServerMCPClient.session() initializes by default, so pass auto_initialize=False when obtaining a session for this function. Passing an already-initialized session raises ValueError rather than re-running the handshake.

There is no way to recover an InitializeResult from a session that is already initialized: the MCP SDK caches only capabilities and discards instructions, serverInfo and protocolVersion.

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Parameters