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# InferenceFunctionDescriptor

A description of an inference function’s signature.

```
struct InferenceFunctionDescriptor
```

## Overview

Use a descriptor to inspect the names and types of a function’s inputs, outputs, and
states before running inference. You obtain a descriptor from
[`functionDescriptor(for:)`](/documentation/CoreAI/AIModel/functionDescriptor(for:))
or from the [`descriptor`](/documentation/CoreAI/InferenceFunction/descriptor) property.

## Topics

### Identifying the function

[`name`](/documentation/CoreAI/InferenceFunctionDescriptor/name)

The function’s name.

### Describing inputs

[`inputCount`](/documentation/CoreAI/InferenceFunctionDescriptor/inputCount)

The number of inputs the function accepts.

[`inputNames`](/documentation/CoreAI/InferenceFunctionDescriptor/inputNames)

The names of the function’s inputs.

[`inputDescriptor(of:)`](/documentation/CoreAI/InferenceFunctionDescriptor/inputDescriptor(of:))

Returns the descriptor for the specified input.

### Describing outputs

[`outputCount`](/documentation/CoreAI/InferenceFunctionDescriptor/outputCount)

The number of outputs the function produces.

[`outputNames`](/documentation/CoreAI/InferenceFunctionDescriptor/outputNames)

The names of the function’s outputs.

[`outputDescriptor(of:)`](/documentation/CoreAI/InferenceFunctionDescriptor/outputDescriptor(of:))

Returns the descriptor for the specified output.

### Describing state

[`stateNames`](/documentation/CoreAI/InferenceFunctionDescriptor/stateNames)

The names of the function’s states.

[`stateDescriptor(of:)`](/documentation/CoreAI/InferenceFunctionDescriptor/stateDescriptor(of:))

Returns the descriptor for the specified state.

## Relationships

### Conforms To

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

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

---

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