/**
 * Session tracking and cleanup module
 *
 * Manages session state, usage statistics, and memory cleanup
 * to prevent memory leaks in long-running agent instances.
 */
export interface SessionUsage {
    prompt: number;
    completion: number;
    total: number;
}
export interface SessionTrackerConfig {
    /** Max sessions to keep in memory */
    maxSessions?: number;
    /** Session TTL in milliseconds */
    sessionTtlMs?: number;
    /** Cleanup interval in milliseconds */
    cleanupIntervalMs?: number;
}
export declare class SessionTracker {
    private sessionUsage;
    private sessionLastActivity;
    private sessionModels;
    private cleanupInterval?;
    private readonly maxSessions;
    private readonly sessionTtlMs;
    private readonly cleanupIntervalMs;
    constructor(config?: SessionTrackerConfig);
    /**
     * Start periodic cleanup of inactive sessions
     */
    private startCleanupInterval;
    /**
     * Cleanup inactive sessions to prevent memory leak
     */
    private cleanupInactiveSessions;
    /**
     * Update last activity timestamp for a session
     */
    touchSession(sessionKey: string): void;
    /**
     * Get usage for a session
     */
    getUsage(sessionKey: string): SessionUsage | undefined;
    /**
     * Update usage for a session
     */
    updateUsage(sessionKey: string, usage: Partial<SessionUsage>): void;
    /**
     * Set model for a session
     */
    setModel(sessionKey: string, modelId: string): void;
    /**
     * Get model for a session
     */
    getModel(sessionKey: string): string | undefined;
    /**
     * Get all session keys
     */
    getSessionKeys(): string[];
    /**
     * Get total session count
     */
    getSessionCount(): number;
    /**
     * Delete a session
     */
    deleteSession(sessionKey: string): boolean;
    /**
     * Dispose resources (call on shutdown)
     */
    dispose(): void;
}