/**
 * cost-control — Turn-end result compaction and flash-first defaults.
 *
 * Harvested from reasonix Pillar 3 (Cost Control).
 *
 * DeepSeek v4-flash is ~12× cheaper than v4-pro, and tool results that
 * accumulate across turns inflate context (and thus cost) unnecessarily.
 *
 * This module provides:
 * 1. Turn-end auto-compaction of large tool results
 * 2. Context-window pressure detection
 */
import type { DeepSeekChatMessage } from "./types.js";
/** Default token cap per tool result after compaction. */
export declare const RESULT_CAP_TOKENS = 3000;
/** Emergency context pressure threshold (% of window). */
export declare const EMERGENCY_THRESHOLD = 0.8;
/** Proactive shrink threshold. */
export declare const PROACTIVE_THRESHOLD = 0.4;
/**
 * Rough estimate of token count from string length.
 * DeepSeek models use ~4 chars/token for English text.
 */
export declare function estimateTokens(text: string): number;
/**
 * Compact a tool result message to a summary.
 * Truncates to the cap and appends a summary suffix.
 */
export declare function compactToolResult(message: DeepSeekChatMessage, capTokens?: number): DeepSeekChatMessage;
export interface CompactionResult {
    compacted: DeepSeekChatMessage[];
    compactedCount: number;
}
/**
 * Compact all tool messages in the list that exceed the token cap.
 */
export declare function compactToolResults(messages: DeepSeekChatMessage[], capTokens?: number): CompactionResult;
/**
 * Estimate total context usage from the messages array.
 */
export declare function estimateContextUsage(messages: DeepSeekChatMessage[]): number;
/**
 * Check whether context is under pressure.
 * Returns a string indicating the pressure level or null if fine.
 */
export declare function checkContextPressure(currentTokens: number, contextWindow: number): "none" | "proactive" | "emergency";
/**
 * Summarize a tool result for roll-up during compaction.
 * Used when a tool result is too large to keep inline.
 */
export declare function summarizeToolResult(message: DeepSeekChatMessage): string;