/**
 * Updates session config mid-stream. `language_code`, `mode`, `prompt`,
 * `stream_type`, and `endpointing` are boundary-gated: validated on arrival
 * but deferred and applied at the next utterance boundary while an utterance
 * is in progress, so each utterance's partials and final use one consistent
 * config snapshot. The VAD detector knobs (`threshold`,
 * `silence_duration_ms`, `min_speech_duration_ms`) apply immediately on the
 * next VAD rebuild and are ignored under `endpointing=manual`. Changing
 * `stream_type` to/from `simulated` is rejected (`invalid_config`).
 *
 * The server replies with `config.updated` (listing the applied keys), or an
 * `error` with code `invalid_config` on a rejected value.
 */
export interface RealtimeConfigUpdate {
    event: "config.update";
    /** Re-arms auto-LID and resets the sticky language. Boundary-gated. */
    language_code?: string | undefined;
    /** Non-streaming context hint (empty string clears it). Boundary-gated. */
    prompt?: string | undefined;
    /** Non-streaming task selector. Boundary-gated. */
    mode?: RealtimeConfigUpdate.Mode | undefined;
    /** `fast`↔`balanced` swap. Boundary-gated. Changing to/from `simulated` is rejected. */
    stream_type?: RealtimeConfigUpdate.StreamType | undefined;
    /** `vad`/`manual` swap. Boundary-gated. */
    endpointing?: RealtimeConfigUpdate.Endpointing | undefined;
    /** VAD activation threshold; applied immediately (vad only). */
    threshold?: number | undefined;
    /** End-of-turn silence; applied immediately (vad only). */
    silence_duration_ms?: number | undefined;
    /** Minimum speech duration; applied immediately (vad only). */
    min_speech_duration_ms?: number | undefined;
}
export declare namespace RealtimeConfigUpdate {
    /** Non-streaming task selector. Boundary-gated. */
    const Mode: {
        readonly Transcribe: "transcribe";
        readonly Translate: "translate";
        readonly Verbatim: "verbatim";
        readonly Translit: "translit";
        readonly Codemix: "codemix";
    };
    type Mode = (typeof Mode)[keyof typeof Mode];
    /** `fast`↔`balanced` swap. Boundary-gated. Changing to/from `simulated` is rejected. */
    const StreamType: {
        readonly Fast: "fast";
        readonly Balanced: "balanced";
    };
    type StreamType = (typeof StreamType)[keyof typeof StreamType];
    /** `vad`/`manual` swap. Boundary-gated. */
    const Endpointing: {
        readonly Vad: "vad";
        readonly Manual: "manual";
    };
    type Endpointing = (typeof Endpointing)[keyof typeof Endpointing];
}