Using /.well-known/ OAuth endpoints behind custom path on GKE

Question

I am running a simple MCP server (built with FastMCP) behind a gateway on GKE with an custom path defined by an HttpRoute. I am attempting to use the /.well-known/ endpoints for OAuth authentication and authorization. Unfortunately, it seems that the routes for the /.well-known/ endpoints; as well as the other OAuth endpoints /authorize, /token, /register, and /revoke, are all hardcoded in the MCP SDK within mcp/server/auth/routes.py within the create_auth_routes() function.

So, for example...

If my MCP server is deployed at https://{my-gateway}/custom/path/
However, the well-known endpoints are pointing to https://{my-gateway}/.well-known/*, which are obviously returning 404 Not Found responses.

When starting my server, I am passing the 'path' parameter in the mcp.run() command. Using my example above, my run command would look like -- mcp.run(transport="http", host="0.0.0.0", port=8080, path="/custom/path/mcp"). However, this path parameter seems to have zero effect on the OAuth well-known endpoints.

So, the question is... Is this expected behavior, and if so, how should we run MCP servers that use well-knonw OAuth endpoints behind API Proxies (Apigee, APIM, etc) or GKE Gateways that require a custom path?

Additional Context

mcp version -- 1.13.1
fastmcp version -- 2.11.4.dev128+5b433f5

Beginne in mcp/server/auth/routes.py bei create_auth_routes() und verfolge, wie der an mcp.run() übergebene Pfad auf die well-known- und OAuth-Routen angewendet wird. Reproduziere die für GKE beschriebene Bereitstellung mit benutzerdefiniertem Pfad und ermittle anschließend, ob das SDK ein Routenpräfix unterstützt oder ob das dokumentierte Ergebnis die erforderliche Gateway-Konfiguration erläutern sollte. Erledigt ist die Aufgabe, wenn das Verhalten und das unterstützte Setup klar sind.