On Khalidine, wizards and sorcerers enjoy a unique RP-based ability referred to as Magesight. The ability to see the ebb and flow of magical energies is one learned in the earliest part of the mage's apprenticeship.  Sorcerers can also perceive the flows, but are at a slight disadvantage in recognizing them due to their lack of training. This ability is what arcane casters use to recognize the invocations of other mages.

Using magesight is not automatic -- the wizard/sorcerer must state his intentions on the the DM channel, then make a successful concentration roll in order to use the sight; properly focusing takes at least three rounds. Correctly recognizing the magical energies and auras which are perceived requires a successful Spellcraft check.

Truly skilled practitioners will find that over time, they can learn to recognize the unique signatures that powerful casters tend to leave behind in their magic.

This ability is specific to the Wizard, Sorcerer, and Warlock classes. It is somewhat limited in that it only allows the user to see disturbances to the magical flow -- so only arcane spells and enchantments can be detected. Summoned creatures, undead created through arcane means, constructs, created creatures, and sorcerers will also bear an aura of magic. Magesight is blind to the spiritual aura that surrounds all living creatures.

It cannot be used to determine the inner workings of magic to the extent where a new spell can be learned.   However, this is the base skill by which abiltiy to identify the magical properties of items is determined.