diff --git a/litellm/proxy/hooks/mcp_semantic_filter/hook.py b/litellm/proxy/hooks/mcp_semantic_filter/hook.py
index 53a83c59049..9b109c3f908 100644
--- a/litellm/proxy/hooks/mcp_semantic_filter/hook.py
+++ b/litellm/proxy/hooks/mcp_semantic_filter/hook.py
@@ -237,7 +237,7 @@ class SemanticToolFilterHook(CustomLogger):
         return None
     
     @staticmethod
-    def initialize_from_config(
+    async def initialize_from_config(
         config: Optional[Dict[str, Any]],
         llm_router: Optional["Router"],
     ) -> Optional["SemanticToolFilterHook"]:
@@ -282,6 +282,9 @@ class SemanticToolFilterHook(CustomLogger):
                 enabled=True,
             )
             
+            # Build router from MCP registry on startup
+            await semantic_filter.build_router_from_mcp_registry()
+            
             hook = SemanticToolFilterHook(semantic_filter)
             
             verbose_proxy_logger.info(
diff --git a/litellm/proxy/proxy_server.py b/litellm/proxy/proxy_server.py
index d724b88d41c..07598eaff15 100644
--- a/litellm/proxy/proxy_server.py
+++ b/litellm/proxy/proxy_server.py
@@ -800,7 +800,7 @@ async def proxy_startup_event(app: FastAPI):  # noqa: PLR0915
         _config = proxy_config.get_config_state()
         _litellm_settings = _config.get("litellm_settings", {})
         verbose_proxy_logger.debug(f"litellm_settings keys = {list(_litellm_settings.keys())}")
-        ProxyStartupEvent._initialize_semantic_tool_filter(
+        await ProxyStartupEvent._initialize_semantic_tool_filter(
             llm_router=llm_router,
             litellm_settings=_litellm_settings,
         )
@@ -4757,7 +4757,7 @@ class ProxyStartupEvent:
         )
 
     @classmethod
-    def _initialize_semantic_tool_filter(
+    async def _initialize_semantic_tool_filter(
         cls,
         llm_router: Optional[Router],
         litellm_settings: Dict[str, Any],
@@ -4773,7 +4773,7 @@ class ProxyStartupEvent:
         mcp_semantic_filter_config = litellm_settings.get("mcp_semantic_tool_filter", None)
         verbose_proxy_logger.debug(f"Semantic filter config: {mcp_semantic_filter_config}")
         
-        hook = SemanticToolFilterHook.initialize_from_config(
+        hook = await SemanticToolFilterHook.initialize_from_config(
             config=mcp_semantic_filter_config,
             llm_router=llm_router,
         )