/**
 * @license
 * Copyright 2025 Google LLC
 * SPDX-License-Identifier: Apache-2.0
 */
export interface TokenUsageData {
    totalTokensUsed: number;
    lastUpdated: number;
    resetDate?: number;
}
export declare class TokenUsageTracker {
    /**
     * Get current token usage
     */
    static getUsage(): Promise<TokenUsageData>;
    /**
     * Add tokens to usage count
     */
    static addTokenUsage(tokens: number): Promise<void>;
    /**
     * Check if user has exceeded free trial limit
     */
    static hasExceededLimit(): Promise<boolean>;
    /**
     * Get remaining tokens in free trial
     */
    static getRemainingTokens(): Promise<number>;
    /**
     * Get usage percentage (0-100)
     */
    static getUsagePercentage(): Promise<number>;
    /**
     * Reset usage (for testing or admin purposes)
     */
    static resetUsage(): Promise<void>;
    /**
     * Clear usage cache
     */
    static clearUsage(): Promise<void>;
}