export declare function isFallbackEnabled(accountsDirPath: string): boolean;
/**
 * True only when fallback is ON AND it was flipped on by `auto-engage`
 * (not by the user manually). Returns false when fallback is off OR
 * when fallback is on for any other reason.
 */
export declare function isFallbackAutoEngaged(accountsDirPath: string): boolean;
interface SetFallbackOpts {
    /** When true, also marks the flag as engaged-by-auto. Used by
     *  `maybeAutoEngageFallback`. Manual toggles leave it false (default)
     *  so the statusline shows them as "manual API". */
    byAutoEngage?: boolean;
}
/** Toggle fallback; takes the lock itself. Call from CLI handlers /
 *  settings UI / anywhere outside an existing `withLock`. */
export declare function setFallbackEnabled(accountsDirPath: string, enabled: boolean, opts?: SetFallbackOpts): void;
/** Toggle fallback INSIDE an existing `withLock`. Used by callers that
 *  must keep the flip atomic with surrounding state mutations
 *  (passthrough's auto-revert / auto-engage, switcher's switch+flip). */
export declare function setFallbackEnabledInLock(accountsDirPath: string, enabled: boolean, opts?: SetFallbackOpts): void;
export {};