Not just what happened.
What happened first.
Antecedent is a consensus-backed sequence notary. It certifies that one declared public event materially occurred before, after, or was superseded by another — and exposes that certificate to downstream contracts that gate real execution on it.
Ordered relationship, not a single fact
A single page witness cannot safely establish that A preceded B. Antecedent's primitive is the pair — two independently observed events bound by a required relation.
The model never asserts order
When source time is explicit, BEFORE/AFTER/SAME_DAY is derived deterministically in-contract from two independently agreed timestamps — never spoken by the model.
Certificates gate real execution
A downstream Gate contract consumes a VALID certificate to decide executable eligibility — for example, whether a migration execution notice may be published at all.