A pack - as in a ruck style back pack - for a day hunt a half mile from your truck is a waste of weight. Unless you're western hunting and day camping, a big hiking pack doesn't make sense.
For stand hunting - day hunt within a mile or two of my truck - I carry a small "tactical pack" (let's be honest, it's an F'ing purse...) for water/gatorade and food/snacks, plus a drag rope. I have a couple knives, a small first aid kit with Quik-Clot, and my binos inside. All of those could go into my jacket pockets, but I often change jackets during the day, and hate transferring stuff. With the truck so nearby, I really only worry about hauling nourishment and an Oh Schitt Kit. If I take a larger bag on such a short trip, it's because I have a sleeping bag inside planning to keep myself extra warm.
I didn't see many people mention a safety harness. If you're elevated, you need a harness.