import type { OutboundMessage } from '../../channels/transport-types.js';
import type { Config } from '../../config/schema.js';
import type { TTSConfig, TTSAutoMode } from './types.js';
export interface TTSApplyOptions {
    config: TTSConfig | undefined;
    channel: string;
    inboundAudio: boolean;
    /** Resolves summarization LLM when enabled */
    appConfig?: Config;
}
export declare function maybeApplyTtsToPayload(msg: OutboundMessage, options: TTSApplyOptions): Promise<OutboundMessage>;
export declare function isTtsEnabled(config: TTSConfig | undefined): boolean;
export declare function resolveTtsAutoMode(config: TTSConfig | undefined, sessionOverride?: string): TTSAutoMode;