diff --git a/platformshconfig/config.py b/platformshconfig/config.py
index 4bf4cfb..7a808fe 100644
--- a/platformshconfig/config.py
+++ b/platformshconfig/config.py
@@ -280,7 +280,7 @@ def routes(self):
             )
         if not self._routesDef:
             raise NotValidPlatformException(
-                'No routes are defined.  Are you sure you are running on Platform.sh?'
+                'No routes are defined. Are you sure you are running on Platform.sh and not on a worker instance?'
             )
         return self._routesDef