Just like how you introduce police or military terms. Really, no one give a single care on what's actually a commisioner's full responsibility, or petty officer, or inspector, or staff sergeant, or whatever. When you meet a brigadier, both of you really don't need to take a seat and talk about their job extensively. But one thing you have to do is to make sure their appearance and what they do in the story are compatible with their rank. The same thing happens with your whole Hunter's/Guild.
When a peace-keeper hunter matter in an episode, you need to show us what they actually do. Are they diplomat? Guardian of a city? Who knows. If a hunter came and said, "I've come to bargain," I don't think you really need to explain more, readers will understand that what they do is part of a hunter's responsibility.
You can still tell readers directly though. For example, maybe your MC only scratches the surface information of the Guild. They know the Guild can give you missions to hunt monsters, and that's all what matters. But you can introduce us a bit of the Guild's dynamics when he actually joins. What's forbidden, who you must report to, is the hierarchy rigid or loose. Anymore than those I don't believe it's necesarry (unless, of course, they matter to the chapter).
