export type TrajectoryAction = "checkpoint-approve" | "checkpoint-reject" | "pause" | "resume" | "steer" | "stop" | "retry";
export type TrajectoryTarget = {
    kind: "run" | "subagent";
    id: string;
};
export declare function isTrajectoryAction(value: unknown): value is TrajectoryAction;
export declare function isTrajectoryTarget(value: unknown): value is TrajectoryTarget;
export declare function trajectoryActionError(action: TrajectoryAction, target: TrajectoryTarget): string | undefined;