/**
 * Public helpers for aggregating cost/token usage from an event stream or
 * a stored session transcript. These mirror the internal accumulators in
 * run-handle-cost.ts but accept any iterable of AgentEvent — so callers can
 * use them on live streams (`handle.events()`) and on session files read
 * back later (`sessions.read(id).events`) with the same shape.
 */
import type { AgentEvent } from './events.js';
export interface EventCostSummary {
    totalUsd: number;
    inputTokens: number;
    outputTokens: number;
    thinkingTokens: number;
    cachedTokens: number;
    totalTokens: number;
    costEventCount: number;
}
/** Fold every `cost` event in a collection into a single summary. */
export declare function sumCost(events: Iterable<AgentEvent>): EventCostSummary;
/** Async variant — fold cost events as they arrive on a live stream. */
export declare function sumCostAsync(events: AsyncIterable<AgentEvent>): Promise<EventCostSummary>;
/**
 * Filter an event iterable to a single event type, with correct narrowing.
 * `for (const ev of filterEvents(events, 'text_delta')) ev.delta ...`
 */
export declare function filterEvents<T extends AgentEvent['type']>(events: Iterable<AgentEvent>, type: T): Generator<Extract<AgentEvent, {
    type: T;
}>>;
export declare function filterEventsAsync<T extends AgentEvent['type']>(events: AsyncIterable<AgentEvent>, type: T): AsyncGenerator<Extract<AgentEvent, {
    type: T;
}>>;