my $tools = new TOOLS;

$tools->SUPER::Callme(); # it should call the AGENT::Callme
$tools->Callme();

##</code><code>##

package TOOLS;

sub new {
  my ($package) = @_;
  my $self = $package->SUPER::new();
  # do other stuff, or remove this whole sub if
  # you're not acutally doing anything in this 
  # method and let AGENT's new() method do all the work.
  return $self;
}

sub Callme {
  my ($self) = @_;
  $self->SUPER::Callme();
  # do stuff.
}