/**
 * Stage 1: Tool Output Pruning
 *
 * Walk messages backwards, protect recent tool output tokens,
 * replace older tool results with "[Tool result cleared]".
 */
import type { ChatMessage, PruneConfig, PruneResult } from "../../types/index.js";
export declare function pruneToolOutputs(messages: ChatMessage[], config?: PruneConfig): PruneResult;