diff --git a/docs/utils.md b/docs/utils.md
index 6439842f..4167feb9 100644
--- a/docs/utils.md
+++ b/docs/utils.md
@@ -44,3 +44,7 @@ Parameters:
                     compatible options:
                     linux, darwin, cygwin, win32, aix, freebsd
 
+Returns:
+
+    no return, just prints output to STDERR
+
diff --git a/jc/utils.py b/jc/utils.py
index 2b5b72b0..8d83a1b0 100644
--- a/jc/utils.py
+++ b/jc/utils.py
@@ -51,6 +51,10 @@ def compatibility(mod_name, compatible):
         compatible      (list) sys.platform name(s) compatible with the parser
                         compatible options: 
                         linux, darwin, cygwin, win32, aix, freebsd
+
+    Returns:
+
+        no return, just prints output to STDERR
     """
     if sys.platform not in compatible:
         mod = mod_name.split('.')[-1]