Guardrails layers card

| Layer | Control | Example |

|-------|---------|---------|

| Input | Filter + harden system | Strip HTML, block jailbreaks |

| Tools | Allowlist + arg schema | No `delete_*` tools |

| Output | Schema + PII scrub | Require citations array |

**Related:** `add-tool-allowlist` · cheatsheet `prompt-injection-defense`