This is a free-text description field (descr) on a Definition object, holding whatever descriptive text was set for a network-control policy definition that governs discovery-protocol and uplink-failure behavior for a vNIC/vHBA template or service profile. An admin uses it to record human-readable context about that specific Definition instance so its purpose is clear without having to infer it from IDs alone. For example, an admin auditing Definition objects would read this field to see the notes attached to one particular instance rather than a generic label shared by all of them.