/** Cheap predicate for a fence that this viewer can turn into a diagram. */
export declare function textHasDiagram(text: string): boolean;
/** Replace every supported complete fence in `text` with its rendered diagram. */
export declare function transformDiagramFences(text: string, width: number): string;
/** True when any text part of an assistant message carries a supported fence. */
export declare function messageHasDiagram(message: {
    content?: unknown;
}): boolean;
/** Return a shallow clone of an assistant message with every supported fence
 *  rendered inline. Non-text parts (thinking, toolCall) pass through untouched,
 *  and a message without a supported fence keeps the same reference. */
export declare function transformMessageDiagrams<T extends {
    content?: unknown;
}>(message: T, width: number): T;