/**
 * Represents an optional timestamp range filter that may or may not be
 * provided by the caller.
 *
 * This abstraction separates filter presence from filter content, allowing
 * query-building logic to reliably determine whether a range constraint
 * should be applied.
 */
export declare class OptionalTimeRangeFilter {
    private readonly minTimestamp;
    private readonly maxTimestamp;
    /**
     * Creates an optional timestamp range filter.
     *
     * @param minTimestamp - Optional lower bound (inclusive).
     * @param maxTimestamp - Optional upper bound (inclusive).
     */
    constructor(minTimestamp: number | undefined, maxTimestamp: number | undefined);
    /**
     * Whether this filter was explicitly provided by the caller.
     *
     * @returns True if at least one bound is defined.
     */
    get isActive(): boolean;
    /**
     * The MongoDB-compatible range query for this filter.
     *
     * Only defined bounds are included to avoid unintentionally constraining
     * the query.
     *
     * @returns A range query object suitable for use in a filter expression.
     */
    get query(): {
        $gte?: number;
        $lte?: number;
    };
}