Long context, held in one briefing.
Teach the agent who it is, how it should speak, and what it knows. FAQs, policies, product notes, and house rules stay in context for every reply. The briefing can hold a large body of stable knowledge, up to 200,000 words, without splitting it across prompts.
You are the Northshore assistant. Help with plans, booking, and house rules. Never invent prices. If you are unsure, offer to connect them with a person.