Compact handoff memo for later agents.
Explain what the content item appears to contribute, which downstream phase should care, and what must not be inferred yet. For example, an ERD can be structural, a meeting transcript can be requirement-oriented, and one item can be both when annotations contain business rules beside structure.
Downstream semantic roles for this content item.
Empty means the content item should not feed a phase directly. Supporting evidence, metadata-only value, policy limitations, intake gaps, or unsupported content should be explained in memo instead of adding a separate enum here.
Common semantic handoff shared by every user message content metadata branch and by the facade one-shot metadata function.
This surface is intentionally small. It is not the source registry record and must not repeat deterministic facts such as filename, MIME type, content hash, source id, content index, storage location, governance decision, or content id.