What is the scope of an agent's authority based on their mandate?

Primary text

The agent possesses authority only over actions explicitly or customarily permitted by the principal. The scope of authority is determined either by explicit verbal instruction (nutf) or by established custom ('urf). An agent authorized to act within a specific time frame is prohibited from acting before or after that time, as this timing may affect the need or value of the action. This principle is supported by analogy to divinely appointed times of worship, where precedence or delay is impermissible.