import type { TrackedSession, SessionSummary } from "./types";
/**
 * SessionTracker tracks tool usage and delegations across sessions,
 * producing SessionSummary records when sessions end.
 *
 * Usage:
 * - Call `startSession()` when a session begins (or lazily on first tool call)
 * - Call `trackToolStart()` / `trackToolEnd()` on tool.execute.before/after
 * - Call `endSession()` when the session ends → writes summary to JSONL
 */
export declare class SessionTracker {
    private sessions;
    private directory;
    constructor(directory: string);
    /**
     * Start tracking a session. Idempotent — if already tracking, returns existing.
     */
    startSession(sessionId: string): TrackedSession;
    /**
     * Track a tool execution start. Lazily starts the session if needed.
     */
    trackToolStart(sessionId: string, toolName: string, callId: string, agent?: string): void;
    /**
     * Track a tool execution end. Records delegation if it was a task tool.
     */
    trackToolEnd(sessionId: string, toolName: string, callId: string, agent?: string): void;
    /**
     * Set the agent name for a session. Only sets on first call (captures primary agent).
     */
    setAgentName(sessionId: string, agentName: string): void;
    /**
     * Set the model ID for a session. Only sets on first call (captures primary model).
     * Safe to call for untracked sessions (no-op, no throw).
     */
    trackModel(sessionId: string, modelId: string): void;
    /**
     * Accumulate dollar cost from a message into the session total.
     */
    trackCost(sessionId: string, cost: number): void;
    /**
     * Track token usage from a message.updated event.
     * Accumulates all token fields into the session's running totals.
     * Lazily starts the session if needed.
     */
    trackTokenUsage(sessionId: string, tokens: {
        input?: number;
        output?: number;
        reasoning?: number;
        cacheRead?: number;
        cacheWrite?: number;
    }): void;
    /**
     * End a session and persist the summary. Removes the session from tracking.
     * Returns the generated summary, or null if the session wasn't being tracked.
     */
    endSession(sessionId: string): SessionSummary | null;
    /**
     * Check if a session is currently being tracked.
     */
    isTracking(sessionId: string): boolean;
    /**
     * Get the current tracked session data (for inspection/testing).
     */
    getSession(sessionId: string): TrackedSession | undefined;
    /**
     * Get the number of sessions currently being tracked.
     */
    get activeSessionCount(): number;
}
/**
 * Create a new SessionTracker instance.
 */
export declare function createSessionTracker(directory: string): SessionTracker;