import type { Brain } from "../core/types.js";
export interface RoutingBrainOptions {
    /** Which field of the Model selects the route. Default "provider". */
    by?: "provider" | "api";
    /** Brain used when no route matches. If omitted, an unmatched model yields an error. */
    fallback?: Brain;
}
/**
 * Route to different brains by a Model field (default `model.provider`). Lets one Runner serve
 * multiple providers/gateways; compose with `createFailoverBrain` for per-route failover.
 *
 * @example
 * createRoutingBrain({
 *   "vllm":   createOpenAIBrain({ baseUrl: VLLM }),
 *   "openai": createOpenAIBrain({ baseUrl: OPENAI, apiKey }),
 * }, { fallback: createOpenAIBrain({ baseUrl: VLLM }) });
 */
export declare function createRoutingBrain(routes: Record<string, Brain>, opts?: RoutingBrainOptions): Brain;