Key features
Core capabilities each platform advertises.
Data not available
- Runtime action validation
- Policy-based guardrails
- Pre-execution blocking
- Structured feedback for self-correction
- Agent action auditing
Updated March 27, 2026
NVIDIA NeMo Guardrails is an open-source toolkit for adding programmable guardrails to LLM applications. It provides a modeling language (Colang) for defining conversation flows, topic boundaries, safety checks, and fact-checking rails. Integrates with any LLM and supports both input and output validation.
Runtime guardrails API that validates AI agent actions against policies before execution, blocking incorrect actions with structured feedback.
Core capabilities each platform advertises.
What each tool does well, and the limitations to keep in mind.
Pros
Cons
Pros
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Choose NeMo Guardrails if you wantChoose if you want
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