Final answer:
A document with mandatory provisions using 'shall' is best described as a regulation, issued by administrative agencies to enforce statutes.
Step-by-step explanation:
A document containing only mandatory provisions using the word "shall" to indicate requirements best describes a regulation. Regulations are rules or directives made and maintained by an authority, and in the context of administrative law, they are typically issued by administrative agencies to explain or enforce a statute. The authority to issue these regulations comes from the executive branch of government. By using "shall," the language is imperative and indicates binding obligations, which is a common characteristic in the drafting of legal documents such as contracts and regulations to express mandatory actions and requirements.