Можно только сократить текст до определенного кол-ва символов
У метода truncated есть 2 параметра
/**
* Text for use with data-ipsTruncate
* Returns the post with paragraphs turned into line breaks
*
* @param bool $oneLine If TRUE, will use spaces instead of line breaks. Useful if using a single line display.
* @param int|null $length If supplied, and $oneLine is set to TRUE, the returned content will be truncated to this length
* @return string
* @note For now we are removing all HTML. If we decide to change this to remove specific tags in future, we can use \IPS\Text\Parser::removeElements( $this->content() )
*/
public function truncated( $oneLine=FALSE, $length=500 )