import type { OutputEvent } from '../../../agent/types.js';
export type LoopStage = 'observing' | 'modeling' | 'choosing' | 'acting' | 'updating';
export interface StageSignals {
    toolErrored?: boolean;
}
export declare const LOOP_STAGES: readonly LoopStage[];
export declare const STAGE_LABEL: Record<LoopStage, string>;
export interface StageTrackerState {
    stage: LoopStage;
    pendingTools: Set<string>;
}
export declare function createStageTracker(): StageTrackerState;
export declare function resetStageTracker(s: StageTrackerState): void;
export declare function advanceStage(s: StageTrackerState, event: OutputEvent): boolean;
export declare function formatStageRail(active: LoopStage, fmt: {
    dim: (s: string) => string;
    accent: (s: string) => string;
    bold: (s: string) => string;
}): string;
export declare class LoopStageBar {
    private readonly stream;
    private readonly getExtraRows;
    private started;
    private currentStage;
    private resizeUnsub;
    private onRowCountChange?;
    constructor(opts: {
        getExtraRows: () => number;
        stream?: NodeJS.WriteStream;
    });
    setRowCountChangeHandler(handler: (rows: number) => void): void;
    start(): void;
    stop(): void;
    repaint(stage: LoopStage): void;
    redraw(): void;
    private clearRow;
}