/**
 * Active tool-call tracking for the long-tool heartbeat. The Codex
 * app-server emits `item/started`/`item/completed` for every item; tool
 * items (`functionCall`/`dynamicToolCall`) bracket one tool execution. The
 * gateway keeps the currently-executing tool so the UI can show "正在执行
 * shell_command · 已运行 X 分 Y 秒" while a long local command runs —
 * without that heartbeat a multi-minute tool execution looks like a hang.
 *
 * @module dsh-subagent-codex-plus/gateway/tool-tracker
 */
/** A Codex tool call currently executing inside the active turn. */
export interface ActiveTool {
    /** Tool name as reported by Codex (e.g. `shell_command`). */
    readonly name: string;
    /** Epoch ms when the tool call started; clients derive the elapsed time. */
    readonly startedAt: number;
}
/**
 * Tracks the currently-executing Codex tool call. Parallel tool starts stack
 * on a counter so the first completion does not clear a still-running tool;
 * the counter also absorbs a completion whose start was missed (e.g. after a
 * mid-turn reconnect) without going negative.
 */
export declare class ActiveToolTracker {
    private count;
    private active;
    /** The tool call currently executing, if any. */
    get current(): ActiveTool | undefined;
    /** Feed an `item/started` notification. */
    onItemStarted(params: Record<string, unknown>, now?: number): void;
    /** Feed an `item/completed` notification. */
    onItemCompleted(params: Record<string, unknown>): void;
    /** Clear on turn boundaries so a stale tool never sticks. */
    reset(): void;
}