/**
 * OpenKernel — Metrics Plugin
 *
 * Subscribes to all events and maintains runtime counters:
 *   missions started/completed/failed, tasks started/completed/failed,
 *   workers spawned/exited, provider changes, recoveries, checkpoints,
 *   total tokens in/out, total duration.
 *
 * Exposes a snapshot() the Dashboard plugin or external monitors can read.
 */
import type { Plugin } from '../types.js';
export interface MetricsSnapshot {
    missionsStarted: number;
    missionsCompleted: number;
    missionsFailed: number;
    tasksStarted: number;
    tasksCompleted: number;
    tasksFailed: number;
    workersSpawned: number;
    workersExited: number;
    providerChanged: number;
    recoveries: number;
    checkpoints: number;
    verificationsPassed: number;
    verificationsFailed: number;
    totalTokensIn: number;
    totalTokensOut: number;
    totalDurationMs: number;
    lastEventAt?: number;
}
export declare function createMetricsPlugin(): Plugin & {
    snapshot(): MetricsSnapshot;
};