Examples of boundaries that should be explicit
- Unknown API or profile version.
- Missing required configuration.
- Capability not present in the reviewed scope.
- Authorization or policy decision denies execution.
- Required dependency is not ready.
Why this helps long-lived OEM integrations
Typed rejection makes change visible to the host and reduces the risk that a future revision is mistaken for a compatible old behavior.
What this page explicitly does not claim: Fail-closed is an architecture principle, not a guarantee that every possible error or threat has already been modeled in every MEMM release.