Use client-vault when the question is scoped to a single client — "what is on John Park's policy", "attach this carrier letter to Maria's file". Use agent-vault for book-wide analytics — "how many MAPD renewals next month".
Tools
client_get— Fetch a single client record.client_list_policies— All policies for a client.client_add_document— Attach a new document (PDF, image).client_search— Search within one client's data.