Which duty requires an agent to keep a detailed account of all property and funds on behalf of the principal?

The duty that requires an agent to keep a detailed account of all property and funds on behalf of the principal is the duty of accounting. This duty is fundamental in the principal-agent relationship because it ensures transparency and trust. Agents are responsible for properly managing the assets they handle and must keep meticulous records of all transactions, including income and expenses related to the principal's assets. This level of accountability helps to protect the principal's interests and facilitates accurate reporting and management of the principal's resources.

Loyalty focuses on the agent's obligation to act in the best interests of the principal, while obedience requires the agent to follow the principal's lawful instructions. Disclosure involves the agent informing the principal of relevant information affecting the agency relationship. Although these duties are also critical in an agency, they do not specifically relate to the systematic accounting of funds and property as required by the duty of accounting.