The four-part test, by control type

✓ meets the property, ~ partial or configuration-dependent, ✗ does not. In-process filters: NeMo, Guardrails AI, LLM Guard. Gateways: Invariant, Bifrost, Falcon AIDR. Policy engines: OPA, Cedar, Strata Maverics. Pre-action: APort, ScopeBlind.