Usage patterns
〈人〉の代理人になるto become someone's representative/agent
He became the president's proxy.
代理人を立てるto appoint an agent or proxy
He appointed an agent to handle the contract.
代理人を通じて〈動詞〉to do something through an agent
The negotiations were carried out through an agent.
〈人〉に代理人を依頼するto ask someone to act as one's agent
I asked a lawyer to act as my agent.
