You explore a new command line tool. You have not bothered to read any of its documentation. For that matter, you don't know what the tool might do. An interactive mode is available, a fact of which you may or may not be aware. You decide to type the command with no arguments.

What should the tool do?
What do you expect?
What would annoy you?
What would you prefer?

Updates:

2010-04-24: I see that some desires are mutually exclusive.

2010-26-06: BrowserUk has an excellent point; slavish conformance to the past is a straightjacket. Several replies note the hazard of typing random commands without first reading the man page, or at least taking the smaller risk of <somecommand -h>. However, I have not chosen to march an animated ASCII Jack-in-the-Box, thumbing its nose, across the terminal window. I have a short usage message now, but I'm keeping the brownie points in mind.

- the lyf so short, the craft so long to lerne -

In reply to CLI Default Action by Xiong

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