import type { string_book } from './string_book';
/**
 * Extracts the teacher-focused instructions from the latest `OPEN` commitment in the book.
 *
 * The `OPEN` commitment may include extra text that should guide the teacher agent when
 * self-learning. We keep the last non-empty `OPEN` value so later overrides win.
 *
 * @param agentSource - The raw agent book source
 * @returns The trimmed instructions or `null` when no instructive `OPEN` commitment exists.
 *
 * @private Internal helper shared between self-learning and related features.
 */
export declare function extractOpenTeacherInstructions(agentSource: string_book): string | null;