public function get_external_parameters() {
        $editorparams = array('text' => new external_value(PARAM_RAW, 'The text for this feedback.'),
                              'format' => new external_value(PARAM_INT, 'The format for this feedback'));
        $editorstructure = new external_single_structure($editorparams, 'Editor structure', VALUE_OPTIONAL);
        return array('assignfeedbackcomments_editor' => $editorstructure);
    }