if @state.has_key?('sms')
        invalid("task sms recipients is missing") unless @state['sms'].has_key?('recipients') && @state['sms']['recipients'].is_a?(String) || @state['sms']['recipients'].is_a?(Array)
        invalid("task sms from is missing") unless @state['sms'].has_key?('from') && @state['sms']['from'].is_a?(String)
        @state['sms']['from'] = interpolate_command(@state['sms']['from'])