You have been given an ability, one you can depend on utterly.
It is a very small ability. Very small. (Like always sharpening pencils perfectly: the lead never breaks in the sharpener, the wood doesn’t split, and the point is ready to begin working with.) You may have had this knack all your life, just never realized how unusual it is. You may have only this moment noticed it. Maybe you were granted an offhand wish.
You can write without telling us what you can do, but do you feel special? Do you envy someone with a sexier gift? Wish it could at least win bar bets for you or save money on laundry? Maybe every time you use it, it gives you a jolt of joy.
You are the one who knows what a small dependable thing means.