/** Options for `runBatch()`. */
export interface BatchOptions {
    /** Items processed at once. Defaults to 3. */
    concurrency?: number;
    /** Stops starting new items after the first failure. Off by default. */
    stopOnError?: boolean;
}
/** The outcome of one batch item. */
export interface BatchItemResult<T> {
    /** The item's position in the input. */
    index: number;
    /** True when the worker returned a value. */
    ok: boolean;
    /** The value returned. */
    value?: T;
    /** Why the worker failed. */
    error?: string;
}
/**
 * Runs a worker over items with bounded concurrency, collecting a result per item in input order.
 * Failures are recorded rather than thrown.
 */
export declare function runBatch<TInput, TOutput>(items: TInput[], worker: (item: TInput, index: number) => Promise<TOutput>, options?: BatchOptions): Promise<Array<BatchItemResult<TOutput>>>;