You touch a willing creature and bestow a limited ability to see into the immediate future. For the duration, the target can't be surprised and has advantage on attack rolls, ability checks, and saving throws. Additionally, other creatures have disadvantage on attack rolls against the target for the duration. This spell immediately ends if you cast it again before its duration ends.
RollQuest ships the D&D 2014 SRD as a content pack, on a 5e character sheet that does the maths - roll from the sheet and let the numbers work themselves out. Free to start.