Or do I have to micromanage that for them? I'd hope they would repair their own gear (I gave Boone a few rifles of the same kind so he can repair them if possible) and tend to other areas of management. Thanks.

Companion gear do not wear out. Unless perhaps in instances when their weapons are directly hit by enemy fire. Personally I have newer seen any of their gear ever degrade. In any case, they can not repair anything.
They don't need to eat. They do not starve.
They can use stimpacks sometimes but only during combat. They autoheal when combat ends.
Some people claim, they can use antidote when poisoned. But I newer saw it.

I had Boone wreck his weapon at least three times...
Unfortunately he just says something and throws it away - so finding the damn thing for fixing it has been nervewracking. It doesn't seem to deteriorate prior to breaking - so there was not any way of preventing it by checking on the weapon condition on a regular base.
Maybe it's some glitch in my game ... But the first time it happened i hadn't used any mods.

Boone have a strange ability to drop whatever weapon he use.

Companions will need to go through healing animation to heal themselves...which is rarely effective.....

They may use antidotes but again I can't confirm this either.

They will hell with stimpacks but against foes they'll need to do so are likely to get killed right after.

Companions are not affected by dehydration, starvation, sleep deprivation or radiation. They won't consume food or drink that you put in their inventory, either. They probably won't use chems either, even though I haven't tried it, and I'm not sure about stimpaks. Weapons and armor do not degrade on them, but it is possible for their weapons to get knocked out of their hands in melee combat. Personally, I had to backtrack more than once to find the Paladin Toaster that was knocked out of Veronica's hands after she punched out another Deathclaw. So the only thing you have to worry about is the weapons you gave them.

There is also the matter of poison. I was recently fighting some Cazadores with Cass and Rex, and sometimes they would get poisoned and their health would drop. I thought a stimpak would prevent them from slowly getting killed by the poison, but I was wrong. Upon using a stimpak, Cass's health would drop down to minus three hundred something because the Cazador poison took off all her health at once. So be careful around those things.

--Companions will use Buffout. You can tell because their hitpoints will register it (365/300 or whatever). However it's just like with stimpacks...they'll only ingest it when they've taken a great deal of damage, thus chances are good as soon as they pop the drug/stim, they'll be on the floor 2 seconds later. However I have taken advantage of it in non-hardcoe, either by healing them rapidly as soon as I see the animation, or simply because they pop back up again before long. haha

--The 'taking something' animation does take a couple seconds. You can see enemy AI doing it too...they kind of bend over at the waist a bit and wave an arm like they're scooping something up.

--I've put all kinds of things in their inventory, keeping watch to see if the number goes down, but I've never seen them use an antivenom or other drug/effect. It's possible such use, even if available, is random and unpredictable (to keep them from being even more powerful). Or buggy.

--All companions, for me at least, do take weapon damage. Not just the insta-broken weapon thing either. I can give them a max repaired gun and at some point notice its condition has only slightly degraded. But again, this is from splash damage/hits, not from 'wearing down' via use. For instance, the weapon may stay in that new, slightly damaged condition for a long time before it happens again.

Yes, using stimpacks on companions is bugged. If they are poisoned, it tends to kill them.

Yeah, that poison/stimpack death bug is terrible, for those who have it. Has anyone come up with a mod-fix for that yet?
I haven't had any problems using stimpacks myself, but that's a bug that would enrage me if I did, for sure.

Thanks folks. No need to load Boone up w/ broken pistols then.

What weapons does he use most effectively- sniper rifle/varmit rifle, and...? I gave him a service rifle, machete, laser rifle, shotgun, and 9mm pistol. We're in the RepConn Facility and he is using the Laser Rifle and machete a lot.

His guns and melee skill are the highest & tagged skills so they eventually get to 100.
He can do ok with energy weapons if they're powerful enough but his energy skill is not very high & never goes up so his accuracy with them is lot lower....guns/rifles are his specialty. He does fine with any bullet gun, doesn't really matter, although companions do have a different movement AI script for pistols/machine guns than for rifles. So what you like him to use is just personal preference. Sniper, All-American/carbine, high dmg. pistol, cowboy repeater, and on and on.

The weapon you give him has to do more dps than his default rifle/what he's already using (based on his skill levels, not on yours - and the game menu shows you dps based on yours, so just give it to him and see if he equips it). So if you want him to use a specific weapon, sometimes you have to remove any other weapon (or its ammo) that's more powerful, from his inventory. Oh, also related...the ammo itself can have an effect on dps, so if he doesn't like a weapon with regular cheap-o ammo he might use it if you give him higher dmg ammo. Weapon mods that affect rate of fire may do so as well. Silencer mods do not work on companions.