/**
 * 5-field envelope for the agent-network local protocol (plano 19).
 * Serialized as JSONL (one JSON object per line) over UDS streams.
 */
export interface Envelope {
    from: string;
    to: string | string[];
    id: string;
    re: string | null;
    body: unknown;
}
/**
 * Generates a UUID v7 — time-ordered, monotonically increasing within the
 * same millisecond. Format:
 *   <48-bit ts ms><4-bit ver=7><12-bit rand><2-bit var=10><62-bit rand>
 */
export declare function uuidv7(): string;
export declare class EnvelopeError extends Error {
    constructor(message: string);
}
export declare function serialize(env: Envelope): string;
export declare function parse(line: string): Envelope;
/** Convenience: builds an envelope with id auto-generated. */
export declare function envelope(from: string, to: string | string[], body: unknown, re?: string | null): Envelope;