Solution: Use separate a managed identity for each agent and environment Assign Azure roles at...

Separate managed identities for each agent and environment remove the need to store application secrets and create independent authorization boundaries. Assigning Azure roles at the resource level further limits each identity to only the Storage resource it requires. This sharply reduces lateral movement compared with a shared application principal or subscription-wide role. Microsoft Foundry and Azure identity guidance consistently recommend identity-based authentication, distinct identities when permissions differ, and the narrowest practical RBAC scope. In current Foundry deployments, the exact identity object may be represented through Microsoft Entra agent identity or a federated managed identity relationship, but the architectural principle in the option is correct. Therefore the solution meets both stated goals and the answer is A, Yes. From a security and governance perspective, the control should be enforced at the narrowest platform boundary that can deterministically block or constrain the action. Relying only on prompt text is weaker because the model can still be induced to behave unexpectedly.

Official Microsoft reference: Microsoft Foundry agent identity

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