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Safety

AI Guardrails Implementation

Definition

AI guardrails are protective systems that constrain LLM behavior by filtering inputs, validating outputs, and enforcing safety policies to prevent harmful or unintended AI responses.

Why It Matters

Guardrails are your safety net. Even well-aligned models can produce harmful outputs in edge cases. Guardrails provide programmatic controls that work regardless of model behavior, ensuring your application stays within acceptable bounds.

Types of Guardrails

Input Guards:

  • Prompt injection detection
  • PII filtering
  • Topic restrictions
  • Length limits

Output Guards:

  • Toxicity detection
  • Factual verification
  • Format validation
  • Sensitive content filtering

Behavioral Guards:

  • Rate limiting
  • Cost controls
  • Action restrictions
  • Human approval gates

Implementation Tools

  • NeMo Guardrails: NVIDIA’s dialogue safety framework
  • Guardrails AI: Open-source validation library
  • Llama Guard: Meta’s safety classifier
  • Azure AI Content Safety: Microsoft’s moderation API
  • Custom LLM Judges: Your own safety classifiers

Best Practices

Layer guardrails (defense in depth). Log all filtered content for analysis. Balance safety with usability. Test guardrails against adversarial inputs. Update as new attack patterns emerge.