Support setting title and description for server and client

[JulianJvn]

Description

The MCP spec schema for Implementation, which is used for clientInfo and serverInfo in InitializeRequestParams and InitializeResult, features the two fields

• title for a human-readable title of the MCP client/server, and
• description for a human-readable description of the MCP client/server.

Curiously, it is not possible to set these basic fields for server and client with the Python SDK.

To be more precise, types.Implementation only supports setting the title (via the superclass BaseMetadata), the description is missing altogether and therefore can't be set for both client and server.

In addition, while the client accepts an Implementation-type client_info object during initialization (so it at least permits setting the title), the server only accepts a server.models.InitializationOptions-type init_options object, which doesn't support neither title nor description.

The feature request is to support setting the title and the description for both clients and servers.

The use case is as the MCP specification says: I'd like to provide human-readable titles and descriptions to MCP hosts.

References

No response

[the-ayyi]

Hi Max, I was planning on tackling the client-side changes. Are you already working on that part, or would you be okay with me picking it up?

[maxisbey]

Hey @woshiyixinke, yea happy for you to take it on if you'd like!

I gave Claude a go at fixing it (here: #1793) but didn't have the time to actually follow through to make sure it's correct, so you can use it as a starting point if that's helpful at all.

[JulianJvn]

This has been fixed with #1634 on main. The fix hasn't been released as of 1.26.0.