Besides changing the view, as suggested, if you’re using sub end : ActionClass('RenderView') {}, Catalyst::Action::RenderView—and you probably should be—then all you have to do is write something to the body and the view processing will be skippped. E.g.–

sub moo : Local Args(0) {
    my ( $self, $c ) = @_;
    $c->response->body("OHAI, COW!");
}
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