Simple RAW for 5e V: The Disadvantage Strikes Back

[E’Tallitnics]

Q79 Is there such a thing as spellcraft? If and how can you identify spells being cast?

A79: “Xanathar’s Guide to Everything” has those rules. A reaction + Arcana check (DC 15 + Spell’s Level) as it’s being cast, or an Action afterwards (same DC formula).