# call

abstract suspend fun call(invocationContext: InvocationContext): CallbackChoice<Unit, Content>

Callback executed before the ADK runner runs.

This is the first callback called in the lifecycle, ideal for global setup or initialization tasks.

#### Return

A CallbackChoice where returning CallbackChoice.Break with custom Content halts execution of the runner and resolves the invocation with that content directly. Returning CallbackChoice.Continue with Unit allows execution to proceed normally.

#### Parameters

invocationContext

The context for the entire invocation, containing session information, the root agent, etc.