import type { Model } from '../old-constants';
/**
 * Check if a model is explicitly defined in the models constant object.
 * This is used to determine if a model should allow fallbacks or support cache control.
 * @param model - The model to check
 * @returns boolean - True if the model is explicitly defined, false otherwise
 */
export declare function isExplicitlyDefinedModel(model: Model): boolean;
