Type Alias BeforeToolCall 

pub type BeforeToolCall = Arc<dyn Fn(BeforeToolCallContext<'_>, CancellationToken) -> BoxFuture<'static, Option<BeforeToolCallResult>> + Send + Sync>;

(context, signal) -> Option<BeforeToolCallResult> — can block a tool call before it runs.

Aliased Type

pub struct BeforeToolCall { /* private fields */ }