import type { ProviderCallContext } from '../../types/lifecycle.js';
import type { SpeechRequest, SpeechResponse, TranscriptionRequest, TranscriptionResponse, VoiceProvider, VoiceProviderInfo } from '../../types/voice.js';
/** Options for the Gemini voice provider. */
export interface GoogleVoiceProviderConfig {
    /** Gemini API key, sent as `x-goog-api-key`. */
    apiKey: string;
    /** API base URL. Defaults to `https://generativelanguage.googleapis.com/v1beta`. */
    baseUrl?: string;
    /** The model that transcribes. Defaults to `gemini-3.8-flash`. */
    transcriptionModel?: string;
    /** The model that speaks. Defaults to `gemini-3.8-flash-tts`. */
    speechModel?: string;
    /** Voice used when a request names none, one of Gemini's prebuilt voices. Defaults to `Kore`. */
    defaultVoice?: string;
    /** Headers added to every request. */
    headers?: Record<string, string>;
    /** Replaces the global `fetch`. */
    fetch?: typeof fetch;
}
/**
 * Gemini speech-to-text and text-to-speech, through `generateContent`: a text model transcribes audio
 * it hears, and a speech model speaks text in one of Gemini's voices, as WAV or raw PCM. Experimental
 * until a live run is recorded.
 */
export declare class GoogleVoiceProvider implements VoiceProvider {
    private readonly config;
    /** Always `google`, with transcription and speech. */
    readonly info: VoiceProviderInfo;
    constructor(config: GoogleVoiceProviderConfig);
    /**
     * Transcribes audio: its words, in the language spoken, and nothing else. `language` and `prompt`
     * guide the model; a request for timings is refused, since Gemini's transcript has none.
     */
    transcribe(request: TranscriptionRequest, context?: ProviderCallContext): Promise<TranscriptionResponse>;
    /**
     * Speaks text in one of Gemini's voices, as WAV, the default, or raw 16-bit PCM. `instructions`, and a
     * `speed` other than 1, direct the delivery as a system instruction, never spoken.
     */
    speak(request: SpeechRequest, context?: ProviderCallContext): Promise<SpeechResponse>;
    /** The audio as a part of the request: a Files API URI by reference, anything else read and sent inline. */
    private audioPart;
    private read;
    private generate;
}