Heat oven to 425° F. In a 9-by-13-inch (or some other large) baking dish, toss the beans and tomatoes with the thyme and oregano sprigs, garlic, red pepper, 1/2 tablespoon of the oil, ½ teaspoon salt, and ¼ teaspoon black pepper.
Pat the chicken dry and place on top of the bean mixture, skin-side up. Rub with the remaining 1/2 tablespoon of oil; season with ½ teaspoon salt and ¼ teaspoon black pepper.
Roast until the chicken is golden and cooked through, 35 to 45 minutes. Sprinkle with the oregano leaves.
Serve with white rice (with parsley and salt) and green beans.