If I run git cl description -d https://chrome-internal-review.googlesource.com/c/252679/ --gerrit in depot_tools, it errors with 

Traceback (most recent call last):
  File "./git_cl.py", line 4871, in <module>
    sys.exit(main(sys.argv[1:]))
  File "./git_cl.py", line 4853, in main
    return dispatcher.execute(OptionParser(), argv)
  File "/s/depot_tools/subcommand.py", line 252, in execute
    return command(parser, args[1:])
  File "./git_cl.py", line 3304, in CMDdescription
    description = ChangeDescription(cl.GetDescription())
  File "./git_cl.py", line 1219, in GetDescription
    self.description = self._codereview_impl.FetchDescription()
  File "./git_cl.py", line 2177, in FetchDescription
    current_rev = data['current_revision']
TypeError: 'NoneType' object has no attribute '__getitem__'
 

Which I believe is it not getting any info from the gerrit server.

If I run it from the gerrit repo, then it gives me the correct value.

Not sure why this happens, and it's not blocking me right now, but it should probably be fixed.