/**
 * Runtime validation schema and wrapper for OS-native TTS adapter options.
 *
 * @module @nhtio/adk/batteries/tts/native/validation
 *
 * @remarks
 * Validates `NativeTtsAdapterOptions` at construction time. Throws
 * {@link @nhtio/adk/batteries/tts/native!E_INVALID_NATIVE_TTS_OPTIONS} on failure. Every field is
 * optional — a zero-config `new NativeTtsAdapter()` is valid and auto-detects the platform — but
 * unknown top-level keys are rejected (`.unknown(false)`) so typos fail loud. The seam functions
 * (`executor`/`fs`/`tmpdir`/`randomName`/`isAvailable`) are accepted as bare functions (or, for
 * `fs`/`executor`, an object whose members are functions) so unit tests can inject fakes.
 */
import type { NativeTtsAdapterOptions } from "./types";
/**
 * Validator schema for `NativeTtsAdapterOptions`. Every field is optional; unknown top-level keys
 * are rejected. Seam functions are accepted as-is.
 */
export declare const nativeTtsOptionsSchema: import("@nhtio/validation").ObjectSchema<NativeTtsAdapterOptions>;
/**
 * Validates an arbitrary input against {@link nativeTtsOptionsSchema}.
 *
 * @param input - The raw options object to validate (pass `{}` for zero-config).
 * @returns The resolved options object (typed as {@link NativeTtsAdapterOptions}).
 * @throws {@link @nhtio/adk/batteries/tts/native!E_INVALID_NATIVE_TTS_OPTIONS} when invalid.
 */
export declare const validateOptions: (input: unknown) => NativeTtsAdapterOptions;