referal letter from primary physician

could some one give me an example of what the physician referal letter to my insurer should contain?

Hi Susan my doctor wrote why i should have sugery I didnt have to tell him what to write he just typed it up .... put in several problems i have like high blood pressure,spurs,and so on... said would be good for me to do this to have better health .. had no problem with insurance at all ... good luck to you hope all goes well for you Jukee Davis