I am a courier making about 30 stops a day. Do I need to list each stop for the IRS deduction for mileage?

Yes. If you listed, for example, 1st and last stops only, and they were 10 miles apart, but your total mileage was 100 miles, how would you defend the extra 90 miles in an audit? On your tax return, you list only total mileage, but you need to have records to defend that number in case of an audit.

you probably are r'qrd to keep a log of your stops as a courier, yes, that is probably a part of your job

Yes, you have to log each trip. Pain, but yes. First trip out and last trip home are commuting.

yes, document everything you do during your working hours.