/**
 * Default EmbeddingProvider implementation backed by OpenAI's embeddings API.
 *
 * Uses native `fetch` so it works in Cloudflare Workers + Node + browsers
 * without an SDK dependency. Templates pass in the API key (and optionally
 * a custom `baseUrl` for proxies / Azure OpenAI / OpenRouter etc.).
 *
 * Models supported by default:
 *   - `text-embedding-3-small` — 1536d, multilingual, cheapest. **Default.**
 *   - `text-embedding-3-large` — 3072d, multilingual, higher quality.
 *   - `text-embedding-ada-002` — 1536d, legacy (kept for migration paths).
 *
 * See `docs/architecture/catalog-architecture.md` for the design.
 */
import { type EmbeddingProvider } from "./contract.js";
/**
 * Known OpenAI embedding models. Adding a new entry here is the only place
 * to touch when OpenAI ships a new model — `createOpenAIEmbeddingProvider`
 * picks up the dimensions / batch limits automatically.
 */
declare const OPENAI_MODELS: {
    readonly "text-embedding-3-small": {
        readonly dimensions: 1536;
        readonly maxTokensPerInput: 8191;
        readonly maxBatchSize: 2048;
        readonly multilingual: true;
    };
    readonly "text-embedding-3-large": {
        readonly dimensions: 3072;
        readonly maxTokensPerInput: 8191;
        readonly maxBatchSize: 2048;
        readonly multilingual: true;
    };
    readonly "text-embedding-ada-002": {
        readonly dimensions: 1536;
        readonly maxTokensPerInput: 8191;
        readonly maxBatchSize: 2048;
        readonly multilingual: true;
    };
};
export type OpenAIEmbeddingModel = keyof typeof OPENAI_MODELS;
export interface OpenAIEmbeddingProviderOptions {
    /** OpenAI API key. */
    apiKey: string;
    /**
     * Embedding model to use. Default: `text-embedding-3-small`.
     * Switching models is a deliberate `bulkReindex` operation — the catalog
     * plane scopes vector queries to documents matching the active
     * `embedding_model_id`, so mid-migration mixes are handled cleanly.
     */
    model?: OpenAIEmbeddingModel;
    /**
     * Override the API base URL — useful for Azure OpenAI, OpenRouter,
     * a corporate proxy, or any OpenAI-API-compatible service. Default:
     * `https://api.openai.com/v1`.
     */
    baseUrl?: string;
    /**
     * Optional `fetch` override for testing or custom transport. Default:
     * the global `fetch`. Must follow the standard Fetch API contract.
     */
    fetchImpl?: typeof fetch;
    /**
     * Override the model id stamped onto search-index documents. Defaults
     * to `openai/<model>/v1` — keep this stable across deployments so
     * documents stay queryable across instances.
     */
    modelId?: string;
}
/**
 * Build the default OpenAI EmbeddingProvider.
 */
export declare function createOpenAIEmbeddingProvider(options: OpenAIEmbeddingProviderOptions): EmbeddingProvider;
/**
 * Helper that chunks a large input array into batches sized to the model's
 * `maxBatchSize` and concatenates the per-batch results. Use this when
 * embedding more than `maxBatchSize` texts at once.
 */
export declare function embedBatched(provider: EmbeddingProvider, texts: string[]): Promise<number[][]>;
export { OPENAI_MODELS };