/**
 * Whether a batch of independent items engages the batch machinery.
 *
 * `single` means: take today's path — no diagnosis fan-out, no rule
 * pre-read, no topology step. `batch` means: the batch machinery may
 * engage.
 */
export type BatchMode = 'single' | 'batch';
/**
 * The number of items at which the batch machinery engages.
 *
 * Two, because one item is the single-task lane's own case and the batch
 * exists for the case where setup is amortized over more than one.
 */
export declare const BATCH_MODE_MIN_ITEMS = 2;
/**
 * Decide which path a batch of independent items takes.
 *
 * @param itemCount - How many independent items the user handed over.
 * @returns `single` for zero or one item, `batch` for two or more.
 */
export declare function decideBatchMode(itemCount: number): BatchMode;