/** Returns the user's preferred editor command, or undefined if not configured. */
export declare function getEditorCommand(): string | undefined;
export interface OpenInEditorOptions {
    /** File extension for the temp file (default: ".md"). */
    extension?: string;
    /** Custom stdio configuration (default: all "inherit"). */
    stdio?: [number | "inherit", number | "inherit", number | "inherit"];
    /** Keep the file's trailing newline instead of trimming it from the returned text. */
    trimTrailingNewline?: boolean;
}
/**
 * Opens `content` in the user's external editor and returns the edited text.
 * Returns `null` if the editor exits with a non-zero code.
 *
 * The caller is responsible for stopping/starting the TUI around this call.
 */
export declare function openInEditor(editorCmd: string, content: string, options?: OpenInEditorOptions): Promise<string | null>;