D&Dtools1

The air around you seems to glow as the currents of magic running through the world become visible to your eyes.
You gain a +2 insight bonus on dispel checks and caster level checks made to counterspell.
If you have 5 or more ranks in Spellcraft, you also automatically recognize any spell being cast, as though you had succeeded on a Spellcraft check.
You must have line of sight to the caster, but distance is otherwise not a factor.
If you have 15 or more ranks in Spellcraft, you not only recognize any spell being cast, but you also know the caster level of any spell being cast.
Again, you must have line of sight to the caster for this effect to function.