diff --git a/litellm/proxy/_experimental/mcp_server/mcp_server_manager.py b/litellm/proxy/_experimental/mcp_server/mcp_server_manager.py
index b8bf986776e..f107b829a90 100644
--- a/litellm/proxy/_experimental/mcp_server/mcp_server_manager.py
+++ b/litellm/proxy/_experimental/mcp_server/mcp_server_manager.py
@@ -192,6 +192,7 @@ class MCPToolRouteResolved:
     """Exactly one MCP server serves the tool name."""
 
     server: MCPServer
+    kind: Literal["resolved"] = "resolved"
 
 
 @dataclass(frozen=True, slots=True)
@@ -199,6 +200,7 @@ class MCPToolRouteNotFound:
     """No MCP server serves the tool name."""
 
     tool_name: str
+    kind: Literal["not_found"] = "not_found"
 
 
 @dataclass(frozen=True, slots=True)
@@ -207,6 +209,7 @@ class MCPToolRouteAmbiguous:
 
     tool_name: str
     server_ids: frozenset[str]
+    kind: Literal["ambiguous"] = "ambiguous"
 
 
 MCPToolRoute = Union[MCPToolRouteResolved, MCPToolRouteNotFound, MCPToolRouteAmbiguous]
@@ -1550,11 +1553,13 @@ class MCPServerManager:
             openapi_key_prefix = prefix_root + MCP_TOOL_PREFIX_SEPARATOR
             global_mcp_tool_registry.unregister_tools_with_prefix(openapi_key_prefix)
 
-        self.tool_name_to_mcp_server_ids_mapping = {
+        surviving = {
             tool_name: remaining
             for tool_name, owner_ids in self.tool_name_to_mcp_server_ids_mapping.items()
             if (remaining := owner_ids - {server.server_id})
         }
+        self.tool_name_to_mcp_server_ids_mapping.clear()
+        self.tool_name_to_mcp_server_ids_mapping.update(surviving)
 
     def remove_server(self, mcp_server: LiteLLM_MCPServerTable):
         """
diff --git a/litellm/proxy/_experimental/mcp_server/server.py b/litellm/proxy/_experimental/mcp_server/server.py
index 0705c392f7f..e18beadd3bf 100644
--- a/litellm/proxy/_experimental/mcp_server/server.py
+++ b/litellm/proxy/_experimental/mcp_server/server.py
@@ -358,8 +358,6 @@ if MCP_AVAILABLE:
     )
     from litellm.proxy._experimental.mcp_server.mcp_server_manager import (
         MCPServerManager,
-        MCPToolRouteAmbiguous,
-        MCPToolRouteResolved,
         _caller_authorization_fans_out,
         _client_forwarded_authorization_headers,
         _should_strip_caller_authorization,
@@ -2629,7 +2627,7 @@ if MCP_AVAILABLE:
                     name,
                     allowed_server_ids=frozenset(server.server_id for server in allowed_mcp_servers),
                 )
-                if isinstance(route, MCPToolRouteAmbiguous):
+                if route.kind == "ambiguous":
                     candidates = sorted(
                         server.name
                         for server in (
@@ -2648,7 +2646,7 @@ if MCP_AVAILABLE:
                             ),
                         },
                     )
-                mcp_server = route.server if isinstance(route, MCPToolRouteResolved) else None
+                mcp_server = route.server if route.kind == "resolved" else None
             else:
                 mcp_server = global_mcp_server_manager._get_mcp_server_from_tool_name(name)
             if mcp_server is None and requested_server is not None:
diff --git a/tests/test_litellm/proxy/_experimental/mcp_server/test_mcp_server_manager.py b/tests/test_litellm/proxy/_experimental/mcp_server/test_mcp_server_manager.py
index 646c7a835da..1116e3efaf1 100644
--- a/tests/test_litellm/proxy/_experimental/mcp_server/test_mcp_server_manager.py
+++ b/tests/test_litellm/proxy/_experimental/mcp_server/test_mcp_server_manager.py
@@ -3948,7 +3948,7 @@ class TestMCPServerManager:
 
         route = manager.resolve_tool_route("echo")
 
-        assert type(route).__name__ == "MCPToolRouteAmbiguous"
+        assert route.kind == "ambiguous"
         assert route.server_ids == frozenset({"id-alpha", "id-zulu"})
 
     def test_resolve_tool_route_resolves_sole_owner(self):
@@ -3959,13 +3959,13 @@ class TestMCPServerManager:
 
         route = manager.resolve_tool_route("echo")
 
-        assert type(route).__name__ == "MCPToolRouteResolved"
+        assert route.kind == "resolved"
         assert route.server is alpha
 
     def test_resolve_tool_route_reports_unknown_tool(self):
         manager = MCPServerManager()
 
-        assert type(manager.resolve_tool_route("nothing_serves_this")).__name__ == "MCPToolRouteNotFound"
+        assert manager.resolve_tool_route("nothing_serves_this").kind == "not_found"
 
     def test_cleanup_withdraws_only_departing_server_from_shared_tool_name(self):
         """Removing one server must leave a co-owned tool name routable to the survivor."""