I tried it with "and croak" instead of "and die".

#!/usr/local/bin/perl

use strict;
use warnings;
use Carp;
use Net::SFTP::Foreign;

use constant HOST => 'localhost';

my $sftp = Net::SFTP::Foreign->new(HOST, more => '-v');
$sftp->error and croak "Unable to connect: " . $sftp->error;
[download]

Update: Fixed typos