Six essential LLM guardrails that keep AI safe and on track:

1. Topic Restrictions — Prevent LLMs from discussing prohibited subjects
2. Fact-Checking — Verify claims against trusted knowledge bases
3. Bias Protection — Filter demographic and stereotyping biases
4. Data Leak Prevention — Block PII and sensitive data from being exposed
5. Toxicity Filtering — Catch harmful, abusive, or inappropriate language
6. Output Validation — Ensure responses match expected format and constraints

Open-source tools to implement these:

• Guardrails AI — framework for adding structural guardrails to LLM apps
• NeMo Guardrails — NVIDIA toolkit for programmable guardrails

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