Core Service · Output Safety

Guardrails that don't break UX.

Stack Vault's Stack Guardrail enforces output controls in version-controlled YAML — blocking jailbreaks, redacting PII, and stopping unsafe completions in 22ms.

99.7%
Prompt Injection Blocked
22ms
Per-Call Overhead
78+
Prebuilt Policies
0fp
False Positive Floor
Policy Library

Out-of-the-box, then customize

78 prebuilt policies aligned to OWASP LLM Top 10. Extend with YAML or code.

Injection Defense

Multi-layer detection for direct, indirect, and multi-turn prompt injection. Updated weekly with new attack signatures.

PII/PHI Redaction

Inline redaction with reversible tokenization. The model gets placeholders; the user gets cleartext.

Topic Boundaries

Block off-domain conversations, competitor mentions, or regulated advice (medical, legal, financial).

Toxicity Scoring

Multilingual toxicity, harassment, and self-harm detection with configurable thresholds per audience.

Code Output Controls

Strip secrets from generated code. Block imports of vulnerable packages. Sign auto-generated commits.

Audit Mode

Run any policy in shadow mode for 30 days. Tune thresholds against real traffic before enforcing.

Frequently Asked

Questions teams ask before deploying

Straightforward answers about scope, integration, data handling, and rollout.

How fast is enforcement?

P50 22ms, P99 95ms. Streaming-aware: we evaluate policies against partial outputs without waiting for completion.

Can we write custom policies?

Yes. YAML for declarative rules, Python SDK for complex logic. Policies version-controlled and CI-tested.

Do you support OWASP LLM Top 10?

All 10 categories ship with default policies. We update the library when new attack vectors surface.

How do you avoid breaking legitimate queries?

Every policy ships with a precision/recall report against our 2M-prompt benchmark, plus your shadow-mode tuning data.

Ready to See It Live

Test our guardrails on your worst prompts

Send us your red-team corpus. We'll show you what gets through and what doesn't.