modelcontextprotocol
diff --git a/src/mcp/server/auth/routes.py b/src/mcp/server/auth/routes.py
@@ -32,7 +32,11 @@ def validate_issuer_url(url: AnyHttpUrl):
     """
 
     # RFC 8414 requires HTTPS, but we allow localhost HTTP for testing
-    if url.scheme != "https" and url.host != "localhost" and not url.host.startswith("127.0.0.1"):
+    if (
+        url.scheme != "https"
+        and url.host != "localhost"
+        and (url.host is not None and not url.host.startswith("127.0.0.1"))
+    ):
         raise ValueError("Issuer URL must be HTTPS")
 
     # No fragments or query parameters allowed

diff --git a/tests/server/fastmcp/test_func_metadata.py b/tests/server/fastmcp/test_func_metadata.py
@@ -203,6 +203,7 @@ def func_dict_any() -> dict[str, Any]:
 
     meta = func_metadata(func_dict_any)
     assert meta.output_schema == {
+        "additionalProperties": True,
         "type": "object",
         "title": "func_dict_anyDictOutput",
     }