Comment 8 for bug 1557888

@Preeti: If you want to go sure before you start coding, you could ask
on the openstack-dev ML about the desired strategy.
@Melanie: The links you provided in comment #6 left me still a little
clueless if there is consensus about the behavior. IIUC, Sean and Kevin
weren't on the same page for example.

I think we're all on the same page that a consistent behavior is
desirable. Personally, my expectation from CLI clients in terms of
feedback behavior has 4 levels. Let me describe it with pseudo nova
client calls with increasing verbosity:

   nova --quiet <command> # don't tell my *anything*
   nova <command> # show success or failure (one line)
   nova --verbose <command> # show me details of whats happening
   nova --debug <command> # I'm a developer, I need to know *everything*

Personally (again), I see a one line success|failure message not as
verbose. I don't have the bandwidth to do a (probably long) discussion
on the ML to drive to a consensus about a general strategy.

For this specific bug report here I would be fine with adding a one line
message of the "nova *-delete" commands ("nova agent-delete",
"nova keypair-delete" and probably others too) which don't yet output
any message, as this would decrease the inconsistent behavior with
little negative impact.