/** Thrown when root-exec credentials cannot be persisted in strict (service) mode. */
export declare class CredentialStorageError extends Error {
    constructor(message: string);
}
/**
 * Production/service installs must fail closed when session or runtime state
 * cannot be written with owner-only permissions. Dev and ad-hoc foreground runs
 * keep the previous best-effort behavior.
 */
export declare function isStrictCredentialStorage(): boolean;
export declare function enforceCredentialStorageWrite(label: string, err: unknown): never;