/** A release selected by the API and delivered inside the PQ-sealed response. */
export interface AgentRelease {
    package: '@forgezero/agent';
    version: string;
    integrity: string;
    tarball: string;
}
export interface UpdateCommand {
    command: string;
    args: readonly string[];
    cwd?: string;
}
export interface UpdateCommandResult {
    exitCode: number;
    output: string;
}
export interface StagedAgentRelease {
    version: string;
    fromVersion: string;
    directory: string;
    previousTarget: string;
    nextTarget: string;
    currentLink: string;
}
export declare const DEFAULT_AGENT_RELEASE_ROOT = "/opt/forgezero/agent";
export declare const DEFAULT_AGENT_CANDIDATE_LINK = "/opt/forgezero/agent/candidate";
export declare const DEFAULT_AGENT_UPDATE_SOCKET = "/run/forgezero-update/helper.sock";
export declare const MAX_AGENT_TARBALL_BYTES: number;
/** Root helper input is data, never a command or filesystem path. */
export declare function validateAgentRelease(release: AgentRelease): AgentRelease;
export declare function compareVersions(left: string, right: string): number;
/**
 * Download, verify and atomically select one self-contained Agent release.
 *
 * The published `fz-agent.js` and `fz.js` are dependency-bundled. No package
 * manager executes lifecycle scripts on a compute, and no mutable global
 * node_modules tree sits underneath a running daemon.
 */
export declare function stageAgentRelease(releaseInput: AgentRelease, options: {
    currentVersion: string;
    root?: string;
    fetch?: typeof globalThis.fetch;
    run?: (input: UpdateCommand) => Promise<UpdateCommandResult>;
}): Promise<StagedAgentRelease>;
/** Select the already-verified immutable directory immediately before restart. */
export declare function selectAgentRelease(staged: StagedAgentRelease): void;
/** Roll back only to the exact link target captured before activation. */
export declare function restoreAgentRelease(staged: StagedAgentRelease): void;
/** Select a verified candidate without changing the active generation. */
export declare function selectAgentCandidate(staged: StagedAgentRelease): void;
export declare function clearAgentCandidate(root?: string): void;