--- a/hgext/histedit.py	Fri Sep 21 00:30:07 2012 +0200
+++ b/hgext/histedit.py	Fri Sep 21 00:30:22 2012 +0200
@@ -306,6 +306,12 @@
 
 
 def makedesc(c):
+    """build a initial action line for a ctx `c`
+
+    line are in the form:
+
+      pick <hash> <rev> <summary>
+    """
     summary = ''
     if c.description():
         summary = c.description().splitlines()[0]