One suggested improvement: you don't really need the "Start" tag... in place of the if/else/Start, this should be sufficient:

unlink "debug.log" if $type eq 'w';
[download]

Actually, even that statement should be unnecessary, too. :-) It looks like it's simple and good for what it does, but is there a reason for creating a separate script like this instead of using the perl debugger or even print statements within the original script?

Update: Ah, sorry, I think I misunderstood how it's to be used. In effect, this is a way of putting print statements in your original script. You may also want to look into Data::Dumper, which will let you print out data for types other than scalar.