AI systems need limits on what they will produce. Guardrails are the combination of training, filters and rules that steer a model away from harmful, unsafe or inappropriate responses, while still letting it be useful for legitimate requests.
Good guardrails block clear harms without being so restrictive that they frustrate ordinary use, a balance that is genuinely hard to strike. People continually probe for ways around them, so the protections are updated over time. They are a necessary layer for deploying AI responsibly, though they work best alongside, not instead of, human oversight for sensitive uses.