It is the nature of stucco to experience some cracking. Small stucco cracks are normal and do not require any maintenance or repair. If a crack exceeds 1/8 inch in width then the crack should be repaired. Repairing of stucco cracks is made by adding a small amount of stucco to the crack. Do not put caulking into cracks. If you experience cracks that are over 1/8 inch in width, you should contact your builder so that the proper resolution can be determined.