Ellyn's Tracking Rune

You inscribe a tracking glyph on a creature or an object that allows you to easily track them. When you cast this spell, an invisible glyph appears in your hand, for the next 10 minutes you can use your action to try apply it on a target, otherwise the spell ends. If you target a creature you may try to touch it as part of a social interaction and hide your real intention, make a Sleight of Hand(Dexterity) check contested by the target's Perception(Wisdom) check which the creature can choose to fail on purpose. If you lose, the creature realizes that you used magic on it and can avoid to be  targeted again for this casting of Ellyn's Tracking Rune. A creature prone to violence might attack you. Another creature might seek retribution in other ways (at the DM's discretion), depending on its nature. If the target has any protection against divination the glyph expires instantly as you attach it and you instead learn that the target has some kind of protection.

When you cast Scrying (or other similar effect that allow you to scry on someone or something) if you target a creature affected by this spell it automatically fails the saving throw. You can also target any object affected by this spell even if Scrying normally doesn't allow that. If the target is on another plane of existance you learn which plane is it and the casting of Scrying ends. 

The glyph is nearly invisible and requires a successful Intelligence (Investigation) check against your spell save DC to be found.