import { LangMessage, LangMessages } from "../messages.ts";
/**
 * Handles streaming events from the Anthropic Messages API and keeps
 * LangMessages in sync with streamed content.
 */
export declare class AnthropicStreamHandler {
    private messages;
    private onResult?;
    private currentAssistantMessage?;
    private textBlocks;
    private reasoningBlocks;
    private toolBlocks;
    private toolArgBuffers;
    constructor(messages: LangMessages, onResult?: (result: LangMessage) => void);
    setOnResult(onResult?: (result: LangMessage) => void): void;
    handleEvent(data: any): void;
    private ensureAssistantMessage;
    private handleMessageStart;
    private handleContentBlockStart;
    private handleContentBlockDelta;
    private handleMessageStop;
    private getOrCreateTextItem;
    private getOrCreateReasoningItem;
    private createToolItem;
    private applyToolDelta;
    private tryParseToolArguments;
    private finalizeToolArguments;
}