Tool

Kotlin |Java

@Target(allowedTargets = [AnnotationTarget.FUNCTION])
@Retention(value = AnnotationRetention.RUNTIME)
annotation Tool

Annotates a function to register it as a Tool that can be called by the generative model.

Summary

Public constructors
`Tool(name: String, description: String)`

Public properties
`String`	`description` A detailed description of what the tool does, used by the model to determine when to call it.
`String`	`name` The name of the tool.

Tool(name: String = "", description: String)

val description: String

A detailed description of what the tool does, used by the model to determine when to call it.

val name: String

The name of the tool. If not specified, the function name will be used.

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Last updated 2026-07-15 UTC.