Quick answer: The four-layer reconciliation compares the API model against the database in four stages. Observed reads the live tables and enforced keys, Modeled assigns per-table status with field diffs and impacted operations, Proposed builds an ordered additive migration plan with blockedBy , and Inferred carries link tables, open questions, and safeguards. Each layer builds on the one before rather than jumping straight to a change.

Why reconciliation is layered

A single flat comparison cannot tell you what is real, what differs, what should change, and what is only inferred.…