export type SessionExecutionDerivedState = 'IDLE' | 'WAITING_RESPONSE' | 'STREAMING_OPEN' | 'POST_RESPONSE_GRACE' | 'STALED' | 'UNKNOWN';
type DerivedStateOptions = {
    nowMs?: number;
    waitingTimeoutMs?: number;
    postResponseGraceMs?: number;
};
export type SessionExecutionStateSnapshot = {
    tmuxSessionId: string;
    state: SessionExecutionDerivedState;
    shouldSkipHeartbeat: boolean;
    reason: 'no_state' | 'sse_open' | 'waiting_response' | 'request_timed_out' | 'recent_nonterminal_response' | 'latest_response_stop' | 'client_closed_before_terminal';
    lastRequestId?: string;
    lastRequestAtMs?: number;
    lastRequestWasStream?: boolean;
    lastResponseRequestId?: string;
    lastResponseAtMs?: number;
    lastFinishReason?: string;
    openSseCount: number;
    lastSseOpenAtMs?: number;
    lastSseCloseAtMs?: number;
    lastClientCloseBeforeTerminalAtMs?: number;
};
export declare class SessionExecutionStateTracker {
    private readonly byRequestId;
    private readonly byTmuxSessionId;
    private sequence;
    private nextSeq;
    private ensureTmuxRecord;
    private maybeDeleteRequest;
    private closeOpenSse;
    private prune;
    recordRequestStart(requestId: string, metadata?: Record<string, unknown> | null): void;
    recordJsonResponseComplete(requestId: string, finishReason?: string): void;
    recordSseStreamStart(requestId: string): void;
    recordSseStreamEnd(requestId: string, options?: {
        finishReason?: string;
        terminal?: boolean;
    }): void;
    recordSseClientClose(requestId: string, options?: {
        finishReason?: string;
        terminal?: boolean;
        closeBeforeStreamEnd?: boolean;
    }): void;
    getStateSnapshot(tmuxSessionId: string, options?: DerivedStateOptions): SessionExecutionStateSnapshot;
}
export declare function getSessionExecutionStateTracker(): SessionExecutionStateTracker;
export {};