An agent is someone you ask to act on your behalf. It can be a lawyer, a paralegal, a family member, or a friend. You can ask an agent to go to court for you if the offence you were charged with carries a maximum penalty of 6 months in jail and/or a $5000 fine and is:
The person acting as your agent appears in the court as if they are you.
If your case is indictable (or hybrid and the crown has not elected), you need a "designation of counsel" in order to have your lawyer or their agent appear on your behalf.