-Within each directory on Keep, there is a @.arvados#collection@ file that does not show up with @ls@. Its contents include, for instance, the @portable_data_hash@, which is the same as the Keep locator.
+In the top level directory of each collection, arv-mount provides a special file called @.arvados#collection@ that contains a JSON-formatted API record for the collection. This can be used to determine the collection's @portable_data_hash@, @uuid@, etc. This file does not show up in @ls@ or @ls -a@.