tag-inheritance-is-transitive-union
IN premise
Derived nodes inherit the sorted union of all ancestor `access_tags`, propagating transitively through arbitrarily long justification chains including diamond dependencies.
Summary
When a belief is derived from other beliefs, it automatically picks up all the access control tags from every ancestor in its derivation chain, no matter how deep. This means if a conclusion depends on sources tagged "confidential" and "internal," the conclusion itself gets both tags — and this works even when multiple derivation paths converge on the same node, ensuring nothing slips through.
Dependents
These beliefs depend on this one:
- access-control-is-transitive-subset-gated — Access control enforces transitive subset-based authorization: visibility requires the caller's tags to be a superset of the node's tags, derived nodes inherit the sorted union of all ancestor tags transitively, and enforcement occurs at read boundaries only — write operations are unrestricted.
Details
| Source | entries/2026/04/29/tests-test_access_tags.md |