/**
 * [WHO]: FileCheckpointStore
 * [FROM]: Depends on node:fs/promises, node:path, node:crypto, @catui/agent-core checkpoint contract
 * [TO]: Consumed by SDK callers that opt into cross-process approval checkpoints
 * [HERE]: core/runtime/checkpoint-store.ts - path-confined atomic JSON checkpoint persistence
 */
import type { AgentRunCheckpoint, CheckpointStore } from "@catui/agent-core";
export declare class FileCheckpointStore implements CheckpointStore {
    private readonly directory;
    constructor(directory: string);
    save(checkpoint: AgentRunCheckpoint): Promise<void>;
    consume(id: string, now?: number, validate?: (checkpoint: AgentRunCheckpoint) => boolean): Promise<AgentRunCheckpoint | undefined>;
    delete(id: string): Promise<boolean>;
    private pathFor;
}