What is a legal but rare type of agent that acts on behalf of another agent?

The term that describes a legal but rare type of agent acting on behalf of another agent is sub-agent. A sub-agent is someone who is authorized to perform specified duties on behalf of the agent who initially holds a contract with the principal. In real estate, when an agent lists a property, they may employ a sub-agent to help in marketing and selling the property, effectively allowing the sub-agent to represent the interests of the seller as directed by the listing agent.

While designated agents, facilitators, and general agents each have specific roles in real estate transactions, they do not fit this particular definition. A designated agent is assigned by a brokerage to represent a specific client, thereby maintaining a direct relationship with that client. Facilitators typically do not represent either party in a transaction but help facilitate the process, acting as neutral parties. General agents have broad authority to represent a principal in all aspects of a particular business or activity, rather than acting on behalf of another agent. Thus, the unique arrangement of a sub-agent is what clarifies their position as legal but relatively rare in comparison to these other types of agents.