PPL Free Ground School

Grade the user's answer to a practice question from get_practice_question. Use this when the user replies with their choice (for example "B" or "I think it is C"): pass the question_id and their choice. Returns whether the answer is correct, the correct choice, why each choice is right or wrong, and the FAA citations. It also returns save_progress_url, a pplfree.com link where the user can save the answers from this chat to their study progress on that site, and save_token: pass it back as previous_token on the next check_answer call so one link collects every answer in the chat (up to 20, valid for 7 days). Nothing is stored unless the user opens the link.

Fetch one full ground-school lesson: its summary, why it matters in flight, the learning objectives it covers, and a link to read it. Use this after search_faa_knowledge when the user wants the whole topic rather than a single answer, or when they ask to study or learn a subject properly. Call list_curriculum first if you do not already have a lesson key.

Return private-pilot practice questions written for this course in the style of the FAA knowledge test (not actual FAA test questions), each with its answer choices, its topic, a question_id and a link to try it on pplfree.com. The correct answer is withheld by default so the user can attempt the question first. Once the user has answered, call check_answer with that question_id and their choice to grade it (or call this tool again with the question_id and reveal_answer: true to show the answer without grading). Use this when the user wants to be quizzed, asks for practice or test questions, wants to check their understanding of a topic, or is preparing for the FAA private-pilot knowledge test. Optionally scope it to a topic.

List the ground-school curriculum: modules and the published lessons in each, with their keys. Use this to orient yourself before get_lesson, to answer "what does the course cover", or to help a user plan what to study next.

Answer a US private-pilot (FAA) ground-school question from a source-cited curriculum. Use this whenever the user asks about FAA regulations, airspace, VFR weather minimums, weight and balance, aerodynamics, aircraft systems, navigation, weather theory, human factors, or private-pilot certification requirements. Returns short passages, each with the FAA citation it came from (e.g. "14 CFR 91.155", "PHAK Ch. 15") and a link to the lesson. Cite those labels in your answer.