/**
 * Pass-through async generator over text chunks. In this SDK it yields each input
 * chunk unchanged (no segmentation is applied).
 */
export declare function segmentText<T>(chunks: AsyncIterable<T> | Iterable<T>, _options?: Record<string, unknown>): AsyncGenerator<T, void, unknown>;
/** Options for {@link FormatMetrics} / {@link formatMetrics}. */
export type FormatMetricsOptions = {
    /** Provider names by role (e.g. STT/LLM/TTS). Attached only on the first call. */
    providers?: Record<string, string>;
    /** System instructions for the session. Attached only on the first call. */
    systemInstructions?: string;
};
/**
 * Builds a metrics payload from a snapshot. The `providers` and
 * `systemInstructions` options are attached only on the first call (since they
 * don't change across a session); later calls just return the merged snapshot.
 *
 * Use the {@link formatMetrics} singleton rather than constructing this directly.
 */
export declare class FormatMetrics {
    private _isFirst;
    /**
     * Build a metrics payload from `snapshot`, attaching `options.providers` and
     * `options.systemInstructions` only on the first call.
     */
    call(snapshot?: Record<string, any> | null, options?: FormatMetricsOptions): Record<string, any>;
}
/** Callable form of {@link FormatMetrics}. */
export type FormatMetricsCallable = {
    (snapshot?: Record<string, any> | null, options?: FormatMetricsOptions): Record<string, any>;
};
/** Shared {@link FormatMetrics} instance, exposed as a callable. */
export declare const formatMetrics: FormatMetricsCallable;