Using spellcraft to determine active buffs?

[Zanos]

Context:
I currently off-DM a campaign, generally making short side adventurers that progress the plot in minor ways when the primary-DM is exhausted and can't really make new content, but people still want to RP/Be thieving murder hobos. Everyone playing is pretty new, and this question came up recently. I had small band of undead and an evil cleric hunting a wounded silver dragon, and the Fighter happens to be riding a (very) homebrewed silver dragon that wound up having a fairly powerful breath attack with a couple of metabreath feats. I figured it wouldn't be unreasonable for a party lead by an intelligent cleric throw a protection from cold on himself and his minions. Of course, this resulted in the dragon wasting it's breath attack that round and creating an area where none of the other melee characters could go due to one of his metabreaths, which resulted in the ogre zombies(who had reach) mashing up a couple party members and the druids animal companion dying. This was intentional as the players had been somewhat lacking for challenging encounters. I looked at the spellcraft skill though, and I wanted to make sure the Wizard wasn't being lax for the sake of a challenging encounter.

Actual Question:
The spellcraft skill mentions that you can determine in place spell effects with a DC of 20+spell level, but that you must be able to see or detect the effects of the spell. Most buffs don't mention any visual manifestations, but if someone has an Arcane Sight up, that would allow them to detect all of the spells. The spell specifically mentions that you can make spellcraft checks to determine the school of magic. Is this function of the skill for stuff like "Yes, that green foul smelling cloud is indeed made of acid and you probably shouldn't walk into it", or can you actually use it to determine what buffs something has?

[Thomar_of_Uointer]

Your first assumption is correct, that particular use of Spellcraft is only for use against spells with visible effects (I believe there is a different check at a lower DC if you see and/or hear the spell being cast). Depending on the GM, you could probably get a check to detect that someone had protection from cold up when they got hit by a cold-damage attack and didn't look quite as frostbitten as they should have been.

If a spell doesn't list any visible result of its effects, then Spellcraft is useless. However, like you said, you could always use three rounds of detect magic or just arcane sight to recognize what buffs and enemy caster has up.

[Mikey8625]

I'm Sure i have seen a buff or item that lets you know all the spells active on anyone with a spellcraft check but i cant find it atm :smallannoyed:

[Mikey8625]

Spell Casters Bane is close but only while they are casting.

http://dndtools.eu/spells/complete-mage--58/spellcasters-bane--804/

[Galvin]

You would need Arcane Sight or Greater Arcane Sight to see the buffs in place. If this is D&D 3.5 (and I apologize if you already stated it isn't.) There is a 1st level spell in the Forgotten Realms Campaign Setting Book called Know Protections or Know Defenses, something along those lines. It pretty much does as it is titled, allowing you to know the persons active buff spells and affects. It is a lot lower level of a spell than the Arcane Sight/Greater Arcane Sight. The only downfall is that it must be cast directly upon your target.

[Diarmuid]

Adding support to previous posts.

Spellcraft would like you identify something like a Mirror Image that was in effect, or perhaps a Fire Shield or an Entropic Shield as they have recognizable visual cues.

Mage Armor, Prot Cold, etc dont have any visual cue so noticing it in effect would be difficult without something like Arcane Sight as was mentioned. Detect Magic could help you identify how many auras were on a person, how powerful they are, and what school they were from (given enough time), but not specifically identify a particular spell.

Seeing the spell cast is another thing entirely. Even if the spell has no visible effects, you're keying in on the motions/words/etc the caster is using to cast the spell to identify it at that point.