diff --git a/documentation/specification.md b/documentation/specification.md
index 743f636..015bd10 100644
--- a/documentation/specification.md
+++ b/documentation/specification.md
@@ -46,12 +46,17 @@ E.g. format for "Bash with timestamps".
 
 ## Export
 Dump the contents of histuidb \<file\>
-to stdout using [format]
+to stdout using [format].
 
 ## Init
 Used for printing reasonable default configuration
 for using histui with the selected shell.
 
+The default configuration,
+if possible should have the following features:
++ override history search with invoking histui
++ sync further commands a histuidb
+
 If no shell is specified,
 the available options shall be printed.
 
@@ -165,3 +170,6 @@ R   : 24h time ("HH:MM")
 S   : seconds; 0 padded {04}
 M   : minutes; 0 padded {03}
 T   : ISO 8601 time format ("HH:MM:SS")
+
+# Environment
+HISTUIHIST  : histuidb to be used