interface BunYaml {
    parse(text: string): unknown;
    stringify(value: unknown, replacer: null, indent: number): string;
}
/** The runtime's YAML (Bun's), or `undefined` when this process is not Bun. */
export declare function bunYaml(): BunYaml | undefined;
export interface ClaudeFrontmatter {
    /** What the runtime reads as the frontmatter (`{}` when absent or unparseable). */
    frontmatter: Record<string, unknown>;
    /** The body after the frontmatter (the whole text when there is none). */
    body: string;
    /** Whether the text HAS a frontmatter block by the runtime's own split. */
    matched: boolean;
    /** Set when the block matched and failed to parse both ways (the runtime then reads `{}`). */
    error?: string;
}
/**
 * The runtime's frontmatter SPLIT alone — no YAML needed: `head` is everything the runtime reads as the
 * frontmatter block (a leading BOM included), `body` is what it reads as content. With no block, `head` is
 * empty and `body` is the text as given. The body is exactly what the runtime scans for `@imports`, and
 * the Winter SDK's rule loader splits the same way.
 */
export declare function claudeFrontmatterSplit(text: string): {
    head: string;
    body: string;
};
/** The runtime's reading of a markdown file's frontmatter. `undefined` when no YAML parser is available. */
export declare function parseClaudeFrontmatter(text: string): ClaudeFrontmatter | undefined;
/** The block the strict split captures (its close on a line of its own), or `undefined` when it does not match. */
export declare function strictFrontmatterBlock(text: string): string | undefined;
/**
 * Writes `frontmatter` + `body` as one markdown file and PROVES the runtime reads it back as exactly
 * that object and body — by its own split, by the strict split, and by its own parse. `undefined` when
 * the proof fails (the caller skips the item rather than hand a runtime a file it would read differently).
 */
export declare function serializeClaudeFrontmatter(frontmatter: Record<string, unknown>, body: string): string | undefined;
export {};