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# SystemLanguageModel.Guardrails

A set of controls that flag sensitive content from model input and output.

```
struct Guardrails
```

## Topics

### Getting the guardrail types

[`default`](/documentation/FoundationModels/SystemLanguageModel/Guardrails/default)

Guardrails that default to ensuring that the system blocks unsafe content in prompts and responses.

[`permissiveContentTransformations`](/documentation/FoundationModels/SystemLanguageModel/Guardrails/permissiveContentTransformations)

Guardrails that allow for permissively transforming text input, including potentially unsafe
content, to text responses.

### Handling guardrail errors

[`LanguageModelError.guardrailViolation(_:)`](/documentation/FoundationModels/LanguageModelError/guardrailViolation(_:))

The model’s safety guardrails were triggered by content in a
prompt or the response generated by the model.

## Relationships

### Conforms To

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Sendable`](/documentation/Swift/Sendable)

---

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