import type { Scope } from "./paths.js";
export type Origin = "user" | "self" | "external";
/**
 * Harness-owned note metadata. The eight required keys are always written; the four optional
 * sleep-shift keys survive this layer untouched when present. `[key: string]: unknown` carries
 * any frontmatter key this layer does not know, preserved verbatim across rewrites.
 */
export type NoteMeta = {
    scope: Scope;
    origin: Origin;
    /** Present only while the note is in the wastebasket; serialized as an ISO timestamp. */
    crumpledAt?: string;
    createdAt: number;
    updatedAt: number;
    lastAccessed: number;
    accessCount: number;
    sourceWindow?: string;
    supersedes?: string;
    recurrenceCount?: number;
    recurrenceWindows?: string[];
    /** Project ownership on newly-created session notes; legacy/invalid values are preserved as-is. */
    project?: unknown;
    [key: string]: unknown;
};
/**
 * Format epoch milliseconds as an ISO 8601 string in the host's local time zone with an
 * explicit numeric offset (e.g. 2026-09-15T17:31:45.392+08:00). A UTC host renders
 * "+00:00"; the "Z" designator is never used, and Date.parse round-trips the value.
 */
export declare function localIso(epochMs: number): string;
export declare function isScope(value: unknown): value is Scope;
export declare function isOrigin(value: unknown): value is Origin;
/**
 * Parse a note file. Missing known keys take the defaults (accessCount 0, timestamps now);
 * crumpledAt stays absent until explicitly set, and unknown keys survive untouched.
 */
export declare function parseNote(raw: string, now?: number): {
    meta: NoteMeta;
    body: string;
};
/** Serialize frontmatter + blank line + body. Known keys emit in Design order, extras after. */
export declare function serializeNote(meta: NoteMeta, body: string): string;
/** Strip a leading frontmatter block from user content, so a note body is pure content. */
export declare function stripLeadingFrontmatter(content: string): string;