type CapturePayload = {
    value: number;
    filters?: {
        [category: string]: string;
    };
};
type CaptureResult = {
    success: boolean;
    message: string;
};
export default class Measurely {
    private static API_KEY;
    /**
     * Initializes the Measurely library with an API key.
     * This key is required for authentication when interacting with the API.
     * @param NEW_API_KEY - The API key provided by Measurely.
     */
    static init(NEW_API_KEY: string): void;
    /**
     * Sends a metric to the Measurely API.
     * @param metric_identifier - The metric id or metric name to be tracked.
     * @param payload - The data payload containing the metric value and optional filters.
     * @returns A Promise resolving to a CaptureResult object indicating the operation's outcome.
     */
    static capture(metric_identifier: string, payload: CapturePayload): Promise<CaptureResult>;
}
export {};