import type { InputEnvelope, ProviderModule } from './contracts.js';
type InputMediaType = 'text' | 'image' | 'audio' | 'video' | 'resource';
export declare function assertTextOnlyInput(provider: Pick<ProviderModule, 'name' | 'type'> | null | undefined, input: InputEnvelope): void;
export declare function getDeclaredProviderInputSupport(provider?: Pick<ProviderModule, 'capabilities'> | null): {
    multipart: boolean;
    mediaTypes: Set<InputMediaType>;
};
export declare function assertProviderSupportsDeclaredInput(provider: Pick<ProviderModule, 'name' | 'type' | 'capabilities'> | null | undefined, input: InputEnvelope): void;
export {};
