diff --git a/mercurial/commands.py b/mercurial/commands.py
index 227479f61db9d169c1afea6fa0a9dce7288d4932_bWVyY3VyaWFsL2NvbW1hbmRzLnB5..d4a79e075303dafbe8d226d119f3e9ead1c48d53_bWVyY3VyaWFsL2NvbW1hbmRzLnB5 100644
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -2106,7 +2106,9 @@
         ] + commitopts2,
          _('[OBSOLETED [REPLACEMENT] [REPL... ]'))
 def debugobsolete(ui, repo, precursor=None, *successors, **opts):
-    """create arbitrary obsolete marker"""
+    """create arbitrary obsolete marker
+
+    With no arguments it it display the list obsolescence marker."""
     def parsenodeid(s):
         try:
             # We do not use revsingle/revrange functions here to accept