Analyze Portal

Upon completion of the spell, you determine the number, size, and location of any magical portals within range. Until the spell ends, all portals appear to you to be limned in glowing, spectral strands of magical energy. Each minute you spend studying a portal while this spell is active, you can choose to learn one of the following:

• The common name for the area around the portal’s current destination, and its general location in the world
• A visualization of the immediate area around the portal’s current destination
• The direction of travel the portal allows (one-way or two-way)
• The key or command word required to activate the portal
• Special properties such as user or time restrictions, or multiple destinations
• Any other special circumstances affecting the portal
• The name and appearance of the creature or event that created the portal

If the portal’s destination is random or it cycles, only the current destination is known, and, if special properties are learned,  you learn the fact that the portal has multiple destinations. Most portals do not resist this spell, however a portal’s creator can choose to create a portal which resists attempts to divine its characteristics. If such a portal is discovered, contest your Arcana skill against the creator’s. If you lose the contest, you must wait a level before attempting this spell on the same portal again.

Adapted from the 3e Forgotten Realms Campaign Setting spell and 4e Forgotten Realms Player's Guide ritual of the same name.