diff --git a/doc/developer-guidelines.sgml b/doc/developer-guidelines.sgml
index d5142964..9de0512f 100644
--- a/doc/developer-guidelines.sgml
+++ b/doc/developer-guidelines.sgml
@@ -307,11 +307,11 @@
check_stuff -c5:6
- Critical if "stuff" is outside of 5:6
+ Critical if "stuff" is less than 5 or more than 6
check_stuff -c@10:20
- Critical if "stuff" is less than 10 or over 20
+ OK if stuff is less than 10 or higher than 20, otherwise critical