How much should you tip your meal delivery person?

Being a person who lived off of tips, (more than one type advised,) I can say this is a very needed question.
It does get confusing.
My thought is unless the preparation of the meal requires a large amount of effort on the cooks' side and/or the wait staff, price is something "the house" needs to absorb.
Unless you have a great staff who knows to tip-out the cooks, they normally get left out of the picture. They do, however, make more money on the clock.  So, not too much on the tip but a show of recognition is always appreciated.  Being on the other side of the line, I found my food in the window with a nice presentation and more efficiently.  Some money, a beer or after-work drink they always appreciate. :)

  In a delivery scenario, it would be nice if the drivers split the tips with the in-house cooks.  The drivers do risk their lives trying to dodge gate-locked communities and meals that are delivered cold because of traffic.  Let's not forget about gas, wear and tear on their cars, and their own person...AND, all soon-to-be-diners should take into consideration all the effort put into the meal they are having delivered.
Here, a tip should be on the presentation of the meal and the delivery person in a prompt, yet enjoyable manner.  I'd say 18%.  If you want to break it down to dollars and cents, 10% to the delivery guy and 8% to the cooks at the homestead.
Now, about your online get-up-order-and-go gig we've got goin' on.  Is it a person who knows how to push buttons, receive, order the human cooks , send the delivery guy in the nearest county to your door, fight the gated communities (they are the worst and the most who seem to want their food delivered to their front doors,) the gas, the trauma of traffic, and so on....
These days, are they actually just computers?  I say .... Maybe....
It is a very sad thought but may be a possibility.
No tip for the computer; but, most definitely, yes if it is a person working other computers.
Definitely a tip to physical being who delivered it to your door.  
Common sense tells me, the harder the meal that needs to be made for you, BY A Human, and Delivered,  the more the tip.
Use your best judgment.  If it is a Baked Alaska, being delivered to your door,  40%.  If it is Pizza, 20%.  Don't use the amount of the meal.  Use the preparation and the ability to get it you, unharmed, with a smile, and in a timely fashion as your guide.

*Just some "tips" on "tips." :) ;) This post was edited by Merlin at May 29, 2019 2:04 PM MDT

I tip my prostitute. Not my meal delivery person.

Given that most delivery people are paid like servers. I tip 15-20% of the order.
If I do not want to pay the tip, I will pick it up myself.  

thats up to you, i will usually ask the person if i dont know

I do a bog-standard $5, regardless of price. 

Interesting.  I know I am criticized on here for pointing out patterns common to different age groups. Obviously this is a serious question but seems so weird as I am in my 7th decade and have never had a meal delivered to me! Nor do I know anyone my general age who had meals delivered unless they are infirm and unable to prepare meals.  But some young men at work in their 30s have told me they always have their meals delivered so am thinking it must be more common for young people.  Which I'm sure I will be taken to task for mentioning.  Goodness have never even considered that. I have taken food out from restaurants sometimes but never had it delivered. Which is something I guess we were just not brought up to do.