export declare function isLoopbackBuilderRequestHost(host: string | undefined): boolean;
export declare function isTrustedBuilderRequestHost(host: string | undefined): boolean;
/**
 * The public origin Builder's preview tunnel serves this container from. The
 * tunnel reaches the container over plain-HTTP loopback, so request headers
 * never carry this origin; only the container environment does.
 */
export declare function firstPublicBuilderPreviewOriginFromEnv(): string | null;