Let's say somebody summons a bralani azata and I disarm his +1 scimitar. Does it disappear immediately or remain on the ground at the bralani's feet?
If the scimitar remains on the ground can one of the PCs grab it? Would the scimitar disappear if somebody other than the bralani grabbed it?
Assuming the PC can grab and even use the +1 scimitar then what happens when the bralani disappears? I'd sort of assume that his +1 scimitar goes with him, but the rules seem unclear:
Summoning: A summoning spell instantly brings a creature or object to a place you designate. When the spell ends or is dispelled, a summoned creature is instantly sent back to where it came from, but a summoned object is not sent back unless the spell description specifically indicates this. A summoned creature also goes away if it is killed or if its hit points drop to 0 or lower, but it is not really dead. It takes 24 hours for the creature to reform, during which time it can't be summoned again.When the spell that summoned a creature ends and the creature disappears, all the spells it has cast expire. A summoned creature cannot use any innate summoning abilities it may have.
I'm not trying to prove that you'd get to keep the +1 scimitar. In fact, I'm rather hoping that somebody can prove the opposite. If we consider the equipment to be "part of" the summoned creature then it would be sent back when the creature is.
On the other hand, I wonder what would happen if I summoned the same bralani myself and handed him a +1 holy scimitar so he could help kill the bad guys. If the bralani got killed or otherwise dismissed would my magic scimitar disappear with him, or would it fall to the ground where the bralani was? (granted the latter might not be any better if the bralani was flying over a pool of lava).
Finally, if the holy scimitar would go with the bralani could I summon the same bralani after 24 hours have passed to get the scimitar back? I guess that being chaotic he could refuse to give it to me...maybe I should have summoned a hound archon instead...
I'm not always the DM, so it isn't a case of me allowing or disallowing anything. Are there actual rules, FAQs, errata, etc which say that items which appear with a summoned creature leave with it or that items given to or taken by a summoned creature stay behind when it leaves? If not then I tend to agree with the basic gist of your post but am not sure how I could "prove" it to anybody.
On second thought I see a problem with the weapon disappearing when disarmed though. If items which leave the monster's possession disappear then the bralani will not be able to fire his bow effectively since the arrows should act like the scimitar and disappear when they leave his possession rather than when he is killed or the spell ends. I guess that a summoner of azatas could carry an extra quiver of arrows for just this purpose, but it seems odd that you'd need to.
I don't think there are written rules on this but this is how I would rule:
The bralani and all of its gear have a "summoned" condition. They are extraplanar and only present temporarily. Equipment disappears after the summon spell has expired. The summoned creature disappears immediately if it is "killed", as the spell doesn't allow the creature to be killed... it must be "returned" moments prior to death. (I run this as the creature vanishing as someone's sword bites into its flesh... it goes away at 0 hp, not taking the rest of the damage being dealt.)
Its equipment not being so protected won't stay around because once the creature is returned to its home, the spell has ended, lifting the "summoned" condition from the equipment, similarly returning it.
So a summon using a bow works just fine. Disarming a summon works just fine. The summon can pick up its weapon just fine. You can pick up its weapon just fine and use it if you wish, until the summon spell ends.
That's my table.
That's pretty much how I'd play it except for the part about summoned monsters disappearing before they're killed. I mean, what if you cast a SoD and the summoned monster fails? I think it winks out AS it dies, not right before, but obviously this is splitting hairs and not the primary interest here.
I agree that the items should return or stay where they started (caster's plane or summon's plane). I'm just looking for any rules to "prove" that and haven't come across them so far. I've read that one of the designers once posted that anything eaten by a summoned monster (including PCs) would fall out on the ground when the monster disappeared. I can't find that though, and I don't know if it was an official statement or just an offhand comment.