Section 902. Pleadings; form

(a) All pleadings shall be formal pleadings,
  as in supreme court practice, except that:
    (1) If the plaintiff's cause of action is for money only, the cause of
  action  may  be  set  forth  by  indorsement  upon  the  summons.    The
  indorsement  shall consist of a statement of the nature and substance of
  the cause of action, and the summons in such instance  shall  set  forth
  the  amount  in  which  the plaintiff will take judgment in the event of
  default.  If  the  plaintiff  shall  appear   without   attorney,   such
  indorsement shall be made by the clerk.
    (2)  Where  the  plaintiff's cause of action is for money only and the
  defendant appears without attorney, he may describe his  answer  to  the
  clerk,  who  shall indorse the nature and substance of the answer on, or
  annex it to, the summons.
    (b) If a formal complaint must be or is used, it shall be served  with
  the  summons,  except  that  if  service is made by publication the CPLR
  shall govern.
    (c) The address of the defendant, and that of his attorney if he shall
  appear by attorney, shall be stated with or in the answer.
    (d) The rules may provide, in actions for  money  only  in  designated
  categories  in  which  a party might otherwise proceed by indorsement as
  above provided, that a formal complaint, or a formal  answer,  or  both,
  shall be required.
    (e) The court in any case may, at any time before judgment, on its own
  motion  or  on  the  motion on notice of a party, direct the service and
  filing of a formal pleading.