/**
 * Chat Function
 *
 * Resolves a chat response using the first available method:
 * 1. chatFn (custom function override)
 * 2. chatbot config (remote HTTP API — standalone mode)
 * 3. chatter RAG pipeline (plugin mode), via chatter's prepareChat + answerOnce
 *
 * All three paths are guarded: a throw anywhere along the chain is logged and
 * answered with a generic apology reply rather than propagating, so a
 * failure in one hook can't take down the whole request differently
 * depending on which branch was active. All three resolve that apology from
 * the same `chatError` phrase key, in the caller's detected language - it is
 * spoken on a call and sent as a message, so it is caller-facing copy like
 * any other and does not belong in the code.
 */
import type { Channel, TalkerDependencies } from "../types";
/**
 * Get a chat response
 */
export declare function chat(deps: TalkerDependencies, phoneNumber: string, message: string, channel: Channel): Promise<string>;