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# MLModelDescription

Information about a model, primarily the input and output format for each feature the model expects, and optional metadata.

```
class MLModelDescription
```

## Topics

### Accessing feature descriptions

[`var stateDescriptionsByName: [String : MLFeatureDescription]`](/documentation/CoreML/MLModelDescription/stateDescriptionsByName)

Description of the state features.

[`var inputDescriptionsByName: [String : MLFeatureDescription]`](/documentation/CoreML/MLModelDescription/inputDescriptionsByName)

A dictionary of input feature descriptions, which the model keys by the input’s name.

[`var outputDescriptionsByName: [String : MLFeatureDescription]`](/documentation/CoreML/MLModelDescription/outputDescriptionsByName)

A dictionary of output feature descriptions, which the model keys by the output’s name.

[`class MLFeatureDescription`](/documentation/CoreML/MLFeatureDescription)

The name, type, and constraints of an input or output feature.

### Accessing metadata

[`var classLabels: [Any]?`](/documentation/CoreML/MLModelDescription/classLabels)

An array of labels, which can be either strings or a numbers, for classifier models.

[`var metadata: [MLModelMetadataKey : Any]`](/documentation/CoreML/MLModelDescription/metadata)

A dictionary of the model’s creation information, such as its description, author, version, and license.

[`struct MLModelMetadataKey`](/documentation/CoreML/MLModelMetadataKey)

The set of keys the model uses to store values in its metadata dictionary.

### Accessing prediction names

[`var predictedFeatureName: String?`](/documentation/CoreML/MLModelDescription/predictedFeatureName)

The name of the primary prediction feature output description.

[`var predictedProbabilitiesName: String?`](/documentation/CoreML/MLModelDescription/predictedProbabilitiesName)

The name of the feature output description for all probabilities of a prediction.

### Accessing update descriptions

[`var isUpdatable: Bool`](/documentation/CoreML/MLModelDescription/isUpdatable)

A Boolean value that indicates whether you can update the model with additional training.

[`var trainingInputDescriptionsByName: [String : MLFeatureDescription]`](/documentation/CoreML/MLModelDescription/trainingInputDescriptionsByName)

A dictionary of the training input feature descriptions, which the model keys by the input’s name.

[`var parameterDescriptionsByKey: [MLParameterKey : MLParameterDescription]`](/documentation/CoreML/MLModelDescription/parameterDescriptionsByKey)

A dictionary of the descriptions for the model’s parameters.

[`class MLParameterDescription`](/documentation/CoreML/MLParameterDescription)

A description of a model parameter that includes a default value and a constraint, if applicable.

### Initializers

[`init?(coder: NSCoder)`](/documentation/CoreML/MLModelDescription/init(coder:))

## Relationships

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

### Conforms To

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

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

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

[`NSCoding`](/documentation/Foundation/NSCoding)

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

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

[`NSSecureCoding`](/documentation/Foundation/NSSecureCoding)

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

---

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