/**
 * Shared prefetch helper for embedding models.
 *
 * Consumed by:
 *   - scripts/prefetch-test-models.mjs (CI warm-up)
 *   - src/cli/models.ts (`models prefetch` / `models check` subcommands)
 *
 * Key behaviours:
 *   - Loads via `pipeline('feature-extraction', model, { dtype: 'q8' })`.
 *   - On corrupt-cache / Protobuf / "Unable to get model file" errors: wipes
 *     the model's cache subdir and retries with exponential backoff.
 *   - Probes a 1-token embed to confirm the model actually works end-to-end.
 *   - Returns dim + metadata without leaving the pipeline loaded.
 */
export interface PrefetchOptions {
    /** Maximum load attempts (default 3). */
    maxAttempts?: number;
    /** Base backoff interval in ms — doubles each retry (default 1000). */
    backoffBaseMs?: number;
    /** Override cache root (default: TRANSFORMERS_CACHE ?? HF_HOME). */
    cacheDir?: string;
}
export interface PrefetchResult {
    model: string;
    dim: number;
    attempts: number;
    cachedAt: string;
}
/**
 * Download (if needed) and probe an embedding model.
 *
 * @throws If all attempts fail, throws the last error with an `attempts`
 *         property attached.
 */
export declare function prefetchModel(model: string, opts?: PrefetchOptions): Promise<PrefetchResult>;