diff --git a/cbutil/yaml_util.py b/cbutil/yaml_util.py
index 17f30e5ca157a083387ad475ea51d11845a40455..ccb9720cd19fe4486f82d4918acb3d40aeed0049 100644
--- a/cbutil/yaml_util.py
+++ b/cbutil/yaml_util.py
@@ -2,6 +2,7 @@ import yaml
 
 
 class Reference:
+    """Represents the !reference tags from Gitlab Ci yamls."""
     yaml_tag = '!reference'
 
     def __init__(self, values):