diff --git a/zfs-backup.py b/zfs-backup.py
index e416fdc..6908ed2 100755
--- a/zfs-backup.py
+++ b/zfs-backup.py
@@ -244,6 +244,7 @@ class ZFS:
         ]
 
     @staticmethod
+    # TODO must take a Snapshot object
     def destroy(full_name, *, recursive=False):
         # TODO condition must be "begins with"
         #   or better argument should be a ZFSPath