If I had to select one readiness issue that causes the most trouble in enterprise implementations, I would choose security and permissions, closely followed by governance around agent actions.
The reason is that Customer Service agents are not just knowledge assistants. Once they interact with cases, customers, queues, knowledge, and business processes, identity, Dataverse security, authorization and action governance become part of the agent architecture.
Microsoft's own guidance reinforces this approach: enterprise agents should use scoped roles, controlled environments, DLP/data policies, gated ALM, secure connections and controlled sharing rather than relying on broad administrator permissions.
Architecturally, I would make "Security + Action Governance" a mandatory readiness gate before allowing a Customer Service Copilot agent into UAT or production. That will prevent many of the problems that otherwise appear later as seemingly random agent, tool, connector, or data-access issues.
