Mocks hide failure modes

In CI, upstreams are often stubbed or replayed from fixtures. That proves your client handles the mock — not that timeouts, rate limits, partial JSON, or version skew from a live partner behave the same way when traffic is real.

Schema is necessary, not sufficient

OpenAPI and JSON Schema catch shape errors. They do not catch semantic errors: the right fields present but wrong for the tenant, deprecated paths still accepted, or auth scopes that pass in staging because test data is too clean.

What structured engines change

Verixet's validation surfaces operate on project and change snapshots with explicit missing-context signals — they refuse to invent files or facts you did not supply. Combined with policy modes and request tracing, operators get evidence that matches what automation can enforce, not a green light from a mocked suite alone.