When cast this spell gives an image of your surroundings in exactly the same manner as the clairvoyance ability. Unlike the ability, the spell is not very useful due to the time it takes to cast.
The ingame help reads:
No saving throw. Casting time: 2 rounds. Type of spell: neutral spell. Affecting stats: int. Cast type: information. Spell point cost: 9. Clairvoyance is the ability to be very aware of one's surrounding areas. Normally only special races have this ability, minotaurs for one. This ability can be, however, simulated through magical means. With the correct chant, one can be given a glimpse of his surroundings, as though he had the ability itself.