How to display variable on CLI

I’m trying to limit the the number of calls at once coming in via my IAX provider to my Asterisk box as follows:

exten => s,1,Set(GROUP()=exgn)
exten => s,2,GotoIf($[${GROUP_COUNT()} > 1]?333)

exten => s,333,Answer
exten => s,334,Playtones(busy)
exten => s,335,Wait(5)
exten => s,336,Hangup

This seems to work ok when I set the limit to 1, but if I try 2 it seems to have no effect.

How can I display what Asterisk has for the value of this variable so I can troubleshoot this code?

exten => s,3,noop( ${GROUP_COUNT()} )
should work

You would use the noop command … k+cmd+NoOp