import type { TunnelStage, TunnelStatus } from './TunnelProvider';
/**
 * Tunnel readiness is a sequence, not a boolean.
 *
 * A provider process that started is not a control connection, a control connection is not
 * a published proxy, and a published proxy is not proof that the Gateway is reachable from
 * outside. These helpers keep every provider reporting the same four facts so the UI and
 * the diagnostics never turn "we spawned something" into "the tunnel is up".
 */
export declare function createTunnelStatus(stage: TunnelStage, patch?: Partial<TunnelStatus>): TunnelStatus;
/** Keeps the previous error visible while a provider transitions through a restart. */
export declare function mergeTunnelError(previous: string | undefined, next: string | undefined): string | undefined;
/** Recognizes a missing client binary, which is a deployment fact, not a network failure. */
export declare function describeSpawnError(provider: string, binary: string, error: unknown): string;