import { type JsonObject } from './hub/types/json.js';
export type RuntimeMetadataCarrier = Record<string, unknown> & {
    __rt?: JsonObject;
};
export declare function readRuntimeMetadata(carrier?: Record<string, unknown> | null): JsonObject | undefined;
export declare function ensureRuntimeMetadata(carrier: Record<string, unknown>): JsonObject;
export declare function cloneRuntimeMetadata(carrier?: Record<string, unknown> | null): JsonObject | undefined;
