Depending on the size of your carrots, slice them lengthwise in half or quarters. Drizzle with a bit of olive oil and toss them with the minced garlic and pinches of salt and pepper. Arrange on a baking sheet. Bake for about 20 minutes, flipping halfway through.
Meanwhile, make the yogurt: In a small bowl, combine the yogurt, olive oil, agave, onion, garlic, ginger, lime juice, mustard seeds, cilantro (reserving some for garnish), and a pinch of salt. Stir, taste, and adjust seasonings. Add the reserved cilantro on top for garnish. Refrigerate until ready to serve with the roasted carrots.