/**
 * GrafanaClientRegistry — manages named GrafanaClient instances.
 *
 * Replaces the pattern of each tool factory creating its own GrafanaClient.
 * Clients are created once at startup and looked up by name at tool-call time.
 *
 * For single-instance setups, `get()` with no argument returns the sole client.
 * For multi-instance setups, `get("prod")` targets a specific instance while
 * `get()` returns the configured default.
 */
import { GrafanaClient } from "./grafana-client.js";
import type { ValidatedGrafanaLensConfig } from "./config.js";
export type InstanceInfo = {
    name: string;
    url: string;
    isDefault: boolean;
};
export declare class GrafanaClientRegistry {
    private clients;
    private defaultName;
    constructor(config: ValidatedGrafanaLensConfig);
    /**
     * Get a client by instance name. Pass `undefined` or omit for the default.
     * Throws with available instance names if the name is unknown.
     */
    get(name?: string): GrafanaClient;
    /** Name of the default instance. */
    getDefaultName(): string;
    /** All registered instances with metadata for agent discovery. */
    listInstances(): InstanceInfo[];
    /** True when more than one instance is configured. */
    isMultiInstance(): boolean;
    /** Human-readable list of instance names for error messages and descriptions. */
    formatInstanceNames(): string;
}