/**
 * A tiny typed event emitter.
 *
 * `on` returns an id used to remove the listener again, which is the convention
 * the SDK already used for conversation events.
 */
export declare class Emitter<Events extends Record<string, unknown[]>> {
    private listeners;
    private nextId;
    on<K extends keyof Events>(event: K, listener: (...args: Events[K]) => unknown): string;
    once<K extends keyof Events>(event: K, listener: (...args: Events[K]) => unknown): string;
    off<K extends keyof Events>(event: K, id: string): void;
    emit<K extends keyof Events>(event: K, ...args: Events[K]): void;
    clear(event?: keyof Events): void;
}