MCPServer: expose public get_tool(name) method

[and-win]

Problem

MCPServer has add_tool() and remove_tool() as public methods, but no public get_tool(name) to retrieve a registered tool by name.

ToolManager already exposes a public get_tool(name: str) -> Tool | None:

https://github.com/modelcontextprotocol/python-sdk/blob/main/src/mcp/server/mcpserver/tools/tool_manager.py#L31

But MCPServer._tool_manager is private, so downstream consumers must access mcp._tool_manager.get_tool(name) — which relies on an internal attribute.

Use Case

Downstream projects need to modify a tool's inputSchema after registration. For example, attaching oneOf discriminated action schemas after initial tool registration.

Currently, the only way to get a tool's schema is via list_tools() (returns all tools, must filter by name). There is no way to update a schema without accessing private internals.

Proposed Solution

Add a public method:

class MCPServer:
    def get_tool(self, name: str) -> Tool | None:
        """Get a registered tool by name."""
        return self._tool_manager.get_tool(name)

Optionally, also consider exposing list_tools() directly on MCPServer (currently delegated through _handle_list_tools), and/or an update_tool_input_schema() method for the schema-update use case.

Why This Matters

1. Completeness: add_tool / remove_tool / get_tool form a natural CRUD trio
2. Encapsulation: consumers should not depend on _tool_manager internals
3. Forward compatibility: if _tool_manager is refactored, downstream breaks

Version

mcp==2.0.0b1 — checked that ToolManager.get_tool is already public.

[maxisbey]

Maybe it'd be better to allow you to customize the inputSchema on registration instead?

Could you give me an example of some of the modifications you're need to do to the schema?