export type SourceDocument = {
    pageContent?: string;
    metadata?: {
        source?: string;
    } & Record<string, unknown>;
};
export declare const toValidURL: (url: unknown) => URL | undefined;
export declare const getChatMessageSourceLabel: (url: URL | undefined, source: SourceDocument | null | undefined) => string;
export declare const removeDuplicateURL: (message: {
    sourceDocuments?: unknown;
} | null | undefined) => SourceDocument[];