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# Transcript.ToolDefinition

A definition of a tool.

```
struct ToolDefinition
```

## Topics

### Creating a tool definition

[`init(name: String, description: String, parameters: GenerationSchema)`](/documentation/FoundationModels/Transcript/ToolDefinition/init(name:description:parameters:))

Creates a tool definition with the name, description, and parameter schema you provide.

[`init(tool: some Tool)`](/documentation/FoundationModels/Transcript/ToolDefinition/init(tool:))

Creates a tool definition that describes the tool you provide.

### Inspecting a tool definition

[`var description: String`](/documentation/FoundationModels/Transcript/ToolDefinition/description)

A description of how and when to use the tool.

[`var name: String`](/documentation/FoundationModels/Transcript/ToolDefinition/name)

The tool’s name.

[`var parameters: GenerationSchema`](/documentation/FoundationModels/Transcript/ToolDefinition/parameters)

A schema that specifies the parameters of the tool.

## Relationships

### Conforms To

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

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

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

---

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