import type { GraphDescription } from '../types/graph.js';
/** Anything that can describe itself: a compiled graph, or a description already taken from one. */
export type Describable = GraphDescription | {
    describe(): GraphDescription;
};
/** Options for `toMermaid()`. */
export interface MermaidOptions {
    /** Layout direction. Defaults to top-down. */
    direction?: 'TD' | 'LR';
    /** Draw each subgraph's nodes inside it, or show it as a single node. Defaults to `expand`. */
    subgraphs?: 'expand' | 'collapse';
    /**
     * Nodes to highlight — typically `checkpoint.next` or the nodes of the step being inspected, so a
     * diagram shows where a thread is.
     */
    highlight?: readonly string[];
}
/**
 * Renders a graph as a Mermaid flowchart.
 *
 * Mermaid rather than an image, because GitHub, GitLab, most documentation sites, and many chat tools
 * render it natively, and it diffs as text. For PNG or SVG output, pass the result to any Mermaid
 * renderer; none is bundled, so the graph runtime pays nothing for diagrams.
 *
 * Solid arrows are edges that are always taken, dotted ones are chosen at run time, and a node whose
 * router has neither a mapping nor declared `ends` points at a `?`, because its targets cannot be
 * known without running it.
 */
export declare function toMermaid(graph: Describable, options?: MermaidOptions): string;
/** The description as JSON, for a UI or a test that wants the shape rather than a picture. */
export declare function toGraphJSON(graph: Describable): GraphDescription;