import { type ThreadLink } from './atif.js';
export type TrajectoryMergeReason = 'started_without_terminal' | 'EACCES' | 'ENOSPC' | 'malformed_fragment' | 'identity_hash_drift' | 'unresolvable_subagent_link' | 'unbound_child_fragment' | 'missing_child_fragment' | 'ambiguous_subagent_link' | 'output_path_exists' | 'output_path_not_writable' | 'containment_failure' | 'aggregate_metrics_underivable';
export declare class TrajectoryMergeError extends Error {
    readonly reason: TrajectoryMergeReason;
    constructor(reason: TrajectoryMergeReason, message: string, options?: {
        cause?: unknown;
    });
}
export interface TrajectoryMergeFileSystem {
    readdir(directory: string): string[];
    readFile(filePath: string): Buffer;
    exists(filePath: string): boolean;
    realpath(filePath: string): string;
    access(filePath: string, mode: number): void;
    open(filePath: string, flags: number, mode: number): number;
    write(fd: number, data: Buffer, offset: number, length?: number): number;
    fsync(fd: number): void;
    close(fd: number): void;
    link(source: string, destination: string): void;
    unlink(filePath: string): void;
}
export declare const NODE_TRAJECTORY_MERGE_FS: TrajectoryMergeFileSystem;
export interface MergeTrajectoryOptions {
    trajectoryRoot: string;
    outputPath: string;
    subagentLinks?: ThreadLink[];
}
export interface FragmentOutcome {
    thread_id: string | null;
    state: unknown;
    terminal_reason: unknown;
}
export interface MergeTrajectoryResult {
    outputPath: string;
    sha256: string;
    trajectoryId: string;
    fragments: FragmentOutcome[];
}
export declare function mergeTrajectory(options: MergeTrajectoryOptions, fileSystem?: TrajectoryMergeFileSystem): MergeTrajectoryResult;