Since validationLevel constraint requires all documents to be compliant for optimizations to work, the existence of non-compliant documents on a primary should be treated as data corruption. the validate command should fail and trigger an AF.

The optimizer and execution plans for queries will eventually rely on these schema constraints and could crash a node if they are not held, so it is better to catch it earlier when running the validate command periodically.

The remediation would be to set validationLevel to strict, fix the offending documents, and then set the validationLevel back to constraint.