diff --git a/clientapi/routing/capabilities.go b/clientapi/routing/capabilities.go
index 0c583055e..1792c6308 100644
--- a/clientapi/routing/capabilities.go
+++ b/clientapi/routing/capabilities.go
@@ -29,7 +29,7 @@ func GetCapabilities(
 	req *http.Request, queryAPI roomserverAPI.RoomserverQueryAPI,
 ) util.JSONResponse {
 	roomVersionsQueryReq := roomserverAPI.QueryRoomVersionCapabilitiesRequest{}
-	var roomVersionsQueryRes roomserverAPI.QueryRoomVersionCapabilitiesResponse
+	roomVersionsQueryRes := roomserverAPI.QueryRoomVersionCapabilitiesResponse{}
 	if err := queryAPI.QueryRoomVersionCapabilities(
 		req.Context(),
 		&roomVersionsQueryReq,