/**
 * Twilio Adapter
 *
 * Handles outbound SMS and WhatsApp sending via Twilio's REST API.
 * TwiML generation is handled by src/core/twiml.ts.
 */
import type { TwilioConfig } from "../types";
/**
 * Strip the `whatsapp:` prefix from a phone number if present.
 * Returns the bare phone number (e.g., "+1234567890").
 */
export declare function stripWhatsAppPrefix(phoneNumber: string): string;
/**
 * Options for outbound message sending
 */
export interface SendMessageOptions {
    /** Status callback URL for delivery status updates */
    statusCallback?: string;
}
/**
 * Send an SMS via Twilio REST API
 */
export declare function sendSMS(config: TwilioConfig, to: string, message: string, options?: SendMessageOptions): Promise<boolean>;
/**
 * Send a WhatsApp message via Twilio REST API.
 *
 * Twilio's WhatsApp API uses the same Messages endpoint as SMS but
 * requires `whatsapp:` prefixed From/To numbers.
 */
export declare function sendWhatsApp(config: TwilioConfig, to: string, message: string, options?: SendMessageOptions): Promise<boolean>;