diff -r 14c3afcb1c26 -r 91b2f2176395 hgext/extdiff.py
--- a/hgext/extdiff.py	Wed Jul 27 21:42:24 2016 +0900
+++ b/hgext/extdiff.py	Wed Jul 27 21:44:49 2016 +0900
@@ -325,10 +325,12 @@
     return dodiff(ui, repo, cmdline, pats, opts)
 
 class savedcmd(object):
-    """use %(path)s to diff repository (or selected files)
+    """use external program to diff repository (or selected files)
 
     Show differences between revisions for the specified files, using
-    the %(path)s program.
+    the following program::
+
+        %(path)s
 
     When two revision arguments are given, then changes are shown
     between those revisions. If only one revision is specified then