The writ may be either alternative or peremptory. The alternative writ must state generally the allegation against the party to whom it is directed, and command such party, immediately after the receipt of the writ, or at some other specified time, to do the act required to be performed, or to show cause before the court, at a specified time and place, why he or she has not done so. The peremptory writ must be in some similar form, except the words requiring the party to show cause why he or she has not done as commanded must be omitted and a return day inserted.
RCW 7.16.180