Divination Cantrip
Casting Time: 1 reaction, which you take in response to you or an ally within 10 feet of you failing an ability check
Range: 10 feet
Components: VS
Duration: Instantaneous

You channel magical insight to a creature, potentially turning a failure into success.
Target. One creature within range who failed an ability check.
Effect. The creature can roll a d4 and add the result to the ability check, potentially turning it into a success.
Cantrip Progression. This spell improves in certain ways when you reach higher levels. At 5th level, the range of this spell becomes 30 feet. At 11th level, when the target rolls a 1 on the die granted from this spell, they may re-roll it and use the new result. At 17th level, the range of the spell becomes 60 feet. At 23rd level, the creature can roll a d6 instead of a d4. At 28th level, if the ability check still fails, the creature may add a d6 to its next ability check.

Source: PHB 248, SRD