<prompt> Translate the following text to EnglishMtaalamu mchunguzi atafanya kazi tu ikiwa ana sababu ya kuamini kwamba jambo hilo linaweza kutathminiwa kulingana na vigezo vinavyofaa na vinavyopatikana kwa watumiaji.  <response>: The practitioner auditor shall perform an engagement only if he or she has reason to believe that the subject matter is capable of evaluation against criteria that are suitable and available to users. 