Service of process is jurisdictional, but specific phrasing isn't typically specified by statute. For example, here's the Illinois statute, 735 ILCS 5/2-203(a):
Except as otherwise expressly provided, service of summons upon an individual defendant shall be made (1) by leaving a copy of the summons with the defendant personally, (2) by leaving a copy at the defendant's usual place of abode, with some person of the family or a person residing there, of the age of 13 years or upwards, and informing that person of the contents of the summons, provided the officer or other person making service shall also send a copy of the summons in a sealed envelope with postage fully prepaid, addressed to the defendant at his or her usual place of abode, or (3) as provided in Section 1-2-9.2 of the Illinois Municipal Code with respect to violation of an ordinance governing parking or standing of vehicles in cities with a population over 500,000. The certificate of the officer or affidavit of the person that he or she has sent the copy in pursuance of this Section is evidence that he or she has done so.
The key is that the service of process be completed. Legally, this implies that the server will file an affidavit that describes the circumstances of the legal completion of service. For example, here is a sample affidavit.
Like any other trade, process servers have an association that offers training, publishes a policy manual, and abides by certain best practices.
All that said, the best practices don't specify any specific verbiage. Rather they elaborate a preference for the methods of service (e.g. personal vs. drop) and the like.