I am not going to tip the delivery driver.
Why aren't you going to tip?
It's a food delivery service, they have only given me half my order.
I think if your missing half of it you have the right to be upset. You should let them know that they forgot most of your stuff.
They're the ones making the mistake so they have to give me food for free.
The restaurant could have made the mistake by not giving the driver all of the correct food items. But you should still let them know so you can get what you paid for.