ai-agent-book 精选快照（<2MB 代码与文档，来自 github.com/bojieli/ai-agent-book）

slides/generate.mjs

@@ -0,0 +1,555 @@
+import { copyFile, mkdir, readFile, readdir, rm, writeFile } from "node:fs/promises";
+import { existsSync } from "node:fs";
+import { fileURLToPath } from "node:url";
+import path from "node:path";
+
+import { lessons } from "./course.mjs";
+import {
+  chapter1PilotFigures,
+  chapter1PilotSlideCount,
+  renderChapter1Pilot
+} from "./chapter1-pilot.mjs";
+
+const HERE = fileURLToPath(new URL(".", import.meta.url));
+const REPO = path.resolve(HERE, "..");
+const PUBLIC_IMAGES = path.join(HERE, "public", "images");
+const CJK = new RegExp("[\\u3400-\\u9fff\\uf900-\\ufaff]", "u");
+
+function fail(message) {
+  throw new Error(message);
+}
+
+function yaml(value) {
+  return JSON.stringify(value);
+}
+
+function escapeHtml(value) {
+  return String(value)
+    .replaceAll("&", "&")
+    .replaceAll("<", "&lt;")
+    .replaceAll(">", "&gt;")
+    .replaceAll('"', "&quot;");
+}
+
+function repositoryHref(target) {
+  if (/^(?:https?:|#|mailto:)/.test(target)) return target;
+  return "../" + target.replace(/^\.\//, "");
+}
+
+function cards(items, colors = ["blue", "green", "orange"]) {
+  return [
+    '<div class="grid grid-cols-' + Math.min(items.length, 3) + ' gap-5 mt-6">',
+    ...items.map(([title, text], index) => [
+      '<div class="course-card ' + colors[index % colors.length] + '">',
+      "<h3>" + escapeHtml(title) + "</h3>",
+      "<p>" + escapeHtml(text) + "</p>",
+      "</div>"
+    ].join("\n")),
+    "</div>"
+  ].join("\n");
+}
+
+function slide(options, body, cue) {
+  const hasFrontmatter = Boolean(options.layout || options.className || options.transition);
+  const metadata = ["---"];
+  if (hasFrontmatter) {
+    if (options.layout) metadata.push("layout: " + options.layout);
+    if (options.className) metadata.push("class: " + options.className);
+    if (options.transition) metadata.push("transition: " + options.transition);
+    metadata.push("---");
+  }
+  metadata.push("", body.trim(), "");
+  if (cue) metadata.push("<!-- Presenter cue: " + cue + " -->", "");
+  return metadata.join("\n");
+}
+
+function extensionSlide(chunk, index, total) {
+  const title = total === 1 ? "Continue the experiment" : "Continue the experiment · " + index + "/" + total;
+  const columns = chunk.length > 4 ? 3 : 2;
+  const links = [
+    '<div class="grid grid-cols-' + columns + ' gap-4 mt-6">',
+    ...chunk.map(([label, target]) => [
+      '<a class="course-link" href="' + escapeHtml(repositoryHref(target)) + '">',
+      '<span class="course-link-title">' + escapeHtml(label) + "</span>",
+      '<span class="course-link-path">' + escapeHtml(target) + "</span>",
+      "</a>"
+    ].join("\n")),
+    "</div>"
+  ].join("\n");
+  return slide({}, "# " + title + "\n\n" + links, "Point viewers to the companion paths; do not walk through every extension.");
+}
+
+function demoMinutes(lesson) {
+  return lesson.experiments.reduce((sum, item) => sum + item.duration, 0);
+}
+
+function extensionChunks(lesson) {
+  if (lesson.extensions.length <= 6) return [lesson.extensions];
+  const split = Math.ceil(lesson.extensions.length / 2);
+  return [lesson.extensions.slice(0, split), lesson.extensions.slice(split)];
+}
+
+function isDemoHeavy(lesson) {
+  return demoMinutes(lesson) >= 5;
+}
+
+function movementFor(lesson) {
+  if (lesson.number <= 21) return "Build";
+  if (lesson.number <= 34) return "Improve";
+  return "Expand";
+}
+
+function chapterLessonsFor(lesson) {
+  return lessons.filter((candidate) => candidate.chapter === lesson.chapter);
+}
+
+function isChapterStart(lesson) {
+  return chapterLessonsFor(lesson).at(0)?.number === lesson.number;
+}
+
+function chapterMap(lesson) {
+  const chapterLessons = chapterLessonsFor(lesson);
+  return [
+    '<div class="course-kicker">' + escapeHtml(movementFor(lesson) + " · " + lesson.chapter + " · " + lesson.part) + "</div>",
+    "",
+    "# Problems this chapter will solve",
+    "",
+    cards(chapterLessons.map((candidate) => [
+      "Lesson " + String(candidate.number).padStart(2, "0"),
+      candidate.title
+    ]), ["blue", "green", "purple"])
+  ].join("\n");
+}
+
+function plannedSlideCount(lesson) {
+  const pilotCount = chapter1PilotSlideCount(lesson.number);
+  if (pilotCount !== null) return pilotCount;
+  const extraExtensionSlides = Math.max(0, extensionChunks(lesson).length - 1);
+  const compactedSlides = isDemoHeavy(lesson) ? (isChapterStart(lesson) ? 1 : 2) : 0;
+  return 15 + extraExtensionSlides + (lesson.synthesis ? 1 : 0) - compactedSlides;
+}
+
+function selectedLessonNumbers() {
+  const optionIndex = process.argv.indexOf("--lessons");
+  if (optionIndex === -1) return null;
+  const value = process.argv[optionIndex + 1];
+  if (!value) fail("--lessons requires a comma-separated list such as 2,3");
+  const numbers = value.split(",").map((item) => Number(item.trim()));
+  if (numbers.some((number) => !Number.isInteger(number) || number < 1 || number > lessons.length)) {
+    fail("--lessons values must be integers from 1 to " + lessons.length);
+  }
+  return new Set(numbers);
+}
+
+function lessonDuration(lesson) {
+  return plannedSlideCount(lesson) + demoMinutes(lesson);
+}
+
+function renderLesson(lesson) {
+  const lessonNo = String(lesson.number).padStart(2, "0");
+  const deck = [];
+
+  deck.push([
+    "---",
+    "theme: seriph",
+    "title: " + yaml("Lesson " + lessonNo + " — " + lesson.title),
+    "info: " + yaml("English video course for AI Agents in Depth"),
+    "author: Bojie Li",
+    "transition: slide-left",
+    "mdc: true",
+    "lineNumbers: false",
+    "monaco: false",
+    "aspectRatio: 16/9",
+    "canvasWidth: 980",
+    "layout: cover",
+    "class: cover",
+    "---",
+    "",
+    '<div class="course-kicker">' + escapeHtml(movementFor(lesson) + " · " + lesson.chapter + " · " + lesson.part) + "</div>",
+    "",
+    "# " + lesson.title,
+    "",
+    '<p class="course-subtitle">' + escapeHtml(lesson.subtitle) + "</p>",
+    "",
+    '<div class="course-cover-meta">Lesson ' + lessonNo + " of 42 · " + lessonDuration(lesson) + " minutes · " + escapeHtml(lesson.book) + "</div>",
+    "",
+    "<!-- Presenter cue: Open with the concrete problem. Add personal context in your own words; do not read the slide. -->",
+    ""
+  ].join("\n"));
+
+  if (isChapterStart(lesson) && lesson.chapter !== "Introduction") {
+    deck.push(slide(
+      {},
+      chapterMap(lesson),
+      "Orient viewers to the chapter. Name the progression, then highlight today's first problem."
+    ));
+  } else if (!isDemoHeavy(lesson)) {
+    deck.push(slide(
+      { layout: "center", className: "text-center" },
+      '<div class="course-kicker">The central question</div>\n\n<div class="course-big">' + escapeHtml(lesson.question) + "</div>",
+      "Let the question sit for a moment, then state the failure mode the lesson will explain."
+    ));
+  }
+
+  deck.push(slide(
+    {},
+    "# Why this problem matters\n\n" + cards(lesson.stakes),
+    "Connect each card to a product or experiment consequence."
+  ));
+
+  deck.push(slide(
+    {},
+    "# Three ideas to keep in view\n\n" + cards(lesson.concepts, ["purple", "blue", "green"]),
+    "Define unfamiliar terms in plain language; the audience is new to ML training and RL."
+  ));
+
+  deck.push(slide(
+    {},
+    "# The book's visual model\n\n" +
+      '<img class="course-figure" src="/images/' + escapeHtml(lesson.figure) + '" alt="' + escapeHtml(lesson.figureAlt) + '">\n\n' +
+      '<div class="course-caption">' + escapeHtml(lesson.figureAlt) + "</div>",
+    "Trace the diagram in one direction and name the mechanism that matters for this lesson."
+  ));
+
+  deck.push(slide(
+    {},
+    "# " + escapeHtml(lesson.contrast.leftTitle) + " vs. " + escapeHtml(lesson.contrast.rightTitle) + "\n\n" +
+      '<div class="grid grid-cols-2 gap-6 mt-5">\n' +
+      '<div class="course-card orange"><h3>' + escapeHtml(lesson.contrast.leftTitle) + "</h3><ul>" +
+      lesson.contrast.left.map((item) => "<li>" + escapeHtml(item) + "</li>").join("") +
+      "</ul></div>\n" +
+      '<div class="course-card green"><h3>' + escapeHtml(lesson.contrast.rightTitle) + "</h3><ul>" +
+      lesson.contrast.right.map((item) => "<li>" + escapeHtml(item) + "</li>").join("") +
+      "</ul></div>\n</div>\n\n" +
+      '<div class="course-caption course-caption-strong">' + escapeHtml(lesson.contrast.caption) + "</div>",
+    "Explain the trade-off; avoid presenting the right column as universally superior."
+  ));
+
+  deck.push(slide(
+    {},
+    "# " + lesson.code.title + "\n\n~~~" + lesson.code.lang + "\n" + lesson.code.lines.join("\n") + "\n~~~",
+    "Walk through the executable idea line by line; keep implementation details for the terminal."
+  ));
+
+  const experimentCards = lesson.experiments.map((experiment) => [
+    '<div class="course-card blue">',
+    '<div class="course-demo-head"><span>' + escapeHtml(experiment.id) + "</span><span>" + experiment.duration + " min</span></div>",
+    "<h3>" + escapeHtml(experiment.name) + "</h3>",
+    '<p><strong>Observe:</strong> ' + escapeHtml(experiment.watch) + "</p>",
+    "</div>"
+  ].join("\n"));
+  deck.push(slide(
+    {},
+    "# Test the claim\n\n" +
+      '<div class="grid grid-cols-' + Math.min(lesson.experiments.length, 3) + ' gap-4 mt-5">\n' + experimentCards.join("\n") + "\n</div>\n\n" +
+      (() => {
+        const minutes = demoMinutes(lesson);
+        return '<div class="course-caption course-caption-strong">Demo budget: ' + minutes + " " + (minutes === 1 ? "minute" : "minutes") + " · one contiguous terminal block</div>";
+      })(),
+    "State the prediction before running anything. Name the observation that could disconfirm it."
+  ));
+
+  const commands = lesson.experiments.map((experiment) => "$ " + experiment.command).join("\n\n");
+  deck.push(slide(
+    { className: "course-terminal" },
+    '<div class="course-kicker">Live demo</div>\n\n# Switching to the terminal\n\n~~~bash\n' + commands + "\n~~~\n\n" +
+      '<div class="course-terminal-watch">Run the command(s), narrate decisions, and point to the observation—not just the output.</div>',
+    "Switch windows now. Return to the next slide after every listed experiment is complete."
+  ));
+
+  deck.push(slide(
+    {},
+    "# What the evidence supports\n\n" + cards(lesson.findings.map((item, index) => ["Finding " + (index + 1), item]), ["green", "blue", "purple"]),
+    "Tie each finding to something viewers just observed; distinguish evidence from interpretation."
+  ));
+
+  if (isDemoHeavy(lesson)) {
+    deck.push(slide(
+      {},
+      "# Boundary → design rule\n\n" +
+        '<div class="course-boundary">' + escapeHtml(lesson.boundary) + "</div>\n\n" +
+        '<div class="course-rule">' + escapeHtml(lesson.rule) + "</div>",
+      "State where the evidence stops, then turn that limitation into a reusable engineering rule."
+    ));
+  } else {
+    deck.push(slide(
+      { layout: "center" },
+      '<div class="course-kicker course-kicker-red">Where the claim stops</div>\n\n# Boundary condition\n\n<div class="course-boundary">' + escapeHtml(lesson.boundary) + "</div>",
+      "Say explicitly what this experiment does not establish."
+    ));
+
+    deck.push(slide(
+      { layout: "center" },
+      '<div class="course-kicker">Engineering takeaway</div>\n\n# Design rule\n\n<div class="course-rule">' + escapeHtml(lesson.rule) + "</div>",
+      "Present this as a reusable decision rule, then give one counterexample or trade-off."
+    ));
+  }
+
+  const chunks = extensionChunks(lesson);
+  chunks.forEach((chunk, index) => {
+    deck.push(extensionSlide(chunk, index + 1, chunks.length));
+  });
+
+  if (lesson.synthesis) {
+    deck.push(slide(
+      {},
+      "# The complete course arc\n\n" + cards(lesson.synthesis, ["blue", "green", "purple"]),
+      "Return to the three-part arc from Lesson 1 and connect each stage to evidence viewers saw in the course."
+    ));
+  }
+
+  deck.push(slide(
+    { layout: "center", className: "text-center" },
+    '<div class="course-kicker">Pause and apply</div>\n\n# Your turn\n\n<div class="course-big course-reflection">' + escapeHtml(lesson.reflection) + "</div>",
+    "Invite viewers to pause the video. Offer your own answer after a short beat."
+  ));
+
+  const followingLesson = lessons[lesson.number];
+  const movementEnds = followingLesson && movementFor(followingLesson) !== movementFor(lesson);
+  const chapterEnds = followingLesson && followingLesson.chapter !== lesson.chapter;
+  const nextLabel = lesson.number === lessons.length
+    ? "Course synthesis"
+    : movementEnds
+      ? movementFor(lesson) + " complete · Next · Lesson " + String(lesson.number + 1).padStart(2, "0")
+      : chapterEnds
+        ? lesson.chapter + " complete · Next · Lesson " + String(lesson.number + 1).padStart(2, "0")
+        : "Next · Lesson " + String(lesson.number + 1).padStart(2, "0");
+  if (lesson.number === lessons.length) {
+    deck.push(slide(
+      { layout: "center", className: "text-center" },
+      '<div class="course-kicker">' + nextLabel + '</div>\n\n' +
+        '<div class="course-loop mt-8">\n' +
+        '<div class="course-loop-step blue"><span>1</span><strong>Define the failure</strong></div>\n' +
+        '<div class="course-loop-arrow">→</div>\n' +
+        '<div class="course-loop-step green"><span>2</span><strong>Run a controlled experiment</strong></div>\n' +
+        '<div class="course-loop-arrow">→</div>\n' +
+        '<div class="course-loop-step purple"><span>3</span><strong>Interpret the evidence</strong></div>\n' +
+        '<div class="course-loop-arrow">→</div>\n' +
+        '<div class="course-loop-step orange"><span>4</span><strong>Update safely</strong></div>\n' +
+        '</div>\n\n' +
+        '<div class="course-loop-return">↺ Repeat when new evidence arrives</div>',
+      "Close by tracing the evidence-driven loop from Lesson 1, then leave viewers with the repeat trigger."
+    ));
+  } else {
+    deck.push(slide(
+      { layout: "center", className: "text-center" },
+      '<div class="course-kicker">' + nextLabel + '</div>\n\n<div class="course-next">' + escapeHtml(lesson.next) + '</div>\n\n<div class="course-next-arrow">→</div>',
+      "Use this transition to make the course feel continuous rather than episodic."
+    ));
+  }
+
+  return { markdown: deck.join("\n"), slideCount: deck.length };
+}
+
+function validateLesson(lesson, index) {
+  const required = [
+    "number", "chapter", "part", "title", "subtitle", "book", "figure",
+    "figureAlt", "question", "stakes", "concepts", "contrast", "code", "experiments",
+    "findings", "boundary", "rule", "extensions", "reflection", "next"
+  ];
+  for (const field of required) {
+    if (lesson[field] === undefined || lesson[field] === null || lesson[field] === "") {
+      fail("Lesson " + lesson.number + " is missing " + field);
+    }
+  }
+  if (lesson.number !== index + 1) fail("Lessons must be consecutive at index " + index);
+  if (!lesson.title.endsWith("?")) fail("Lesson " + lesson.number + " must have a problem-oriented question title");
+  if (lesson.stakes.length !== 3 || lesson.concepts.length !== 3 || lesson.findings.length !== 3) {
+    fail("Lesson " + lesson.number + " must have three stakes, concepts, and findings");
+  }
+  if (lesson.experiments.length < 1 || lesson.experiments.length > 3) {
+    fail("Lesson " + lesson.number + " must have one to three experiments");
+  }
+  for (const experiment of lesson.experiments) {
+    for (const field of ["id", "name", "duration", "command", "watch", "mode", "path"]) {
+      if (experiment[field] === undefined || experiment[field] === null || experiment[field] === "") {
+        fail("Lesson " + lesson.number + " experiment is missing " + field);
+      }
+    }
+    if (experiment.duration < 1 || experiment.duration > 3) {
+      fail("Lesson " + lesson.number + " experiment duration must be one to three minutes");
+    }
+  }
+  const target = lessonDuration(lesson);
+  if (target < 15 || target > 20) {
+    fail("Lesson " + lesson.number + " plans " + target + " minutes; expected 15–20");
+  }
+  const visible = JSON.stringify({
+    title: lesson.title,
+    subtitle: lesson.subtitle,
+    book: lesson.book,
+    figureAlt: lesson.figureAlt,
+    question: lesson.question,
+    stakes: lesson.stakes,
+    concepts: lesson.concepts,
+    contrast: lesson.contrast,
+    code: lesson.code,
+    experiments: lesson.experiments,
+    findings: lesson.findings,
+    boundary: lesson.boundary,
+    rule: lesson.rule,
+    extensions: lesson.extensions,
+    synthesis: lesson.synthesis,
+    reflection: lesson.reflection,
+    next: lesson.next
+  });
+  if (CJK.test(visible)) fail("Lesson " + lesson.number + " contains CJK characters in visible metadata");
+  const sourceFigure = path.join(REPO, "book-en", "images", lesson.figure);
+  if (!existsSync(sourceFigure)) fail("Missing figure for Lesson " + lesson.number + ": " + lesson.figure);
+  for (const [, target] of lesson.extensions) {
+    if (!/^(?:https?:|#|mailto:)/.test(target) && !existsSync(path.join(REPO, target))) {
+      fail("Lesson " + lesson.number + " links a missing extension: " + target);
+    }
+  }
+  for (const experiment of lesson.experiments) {
+    if (!existsSync(path.join(REPO, experiment.path))) {
+      fail("Lesson " + lesson.number + " links a missing experiment path: " + experiment.path);
+    }
+  }
+}
+
+function outline() {
+  const groups = [];
+  for (const lesson of lessons) {
+    const current = groups.at(-1);
+    if (!current || current.chapter !== lesson.chapter) {
+      groups.push({ chapter: lesson.chapter, lessons: [lesson] });
+    } else {
+      current.lessons.push(lesson);
+    }
+  }
+  const allocationRows = groups.map(({ chapter, lessons: chapterLessons }) => {
+    const first = chapterLessons.at(0).number;
+    const last = chapterLessons.at(-1).number;
+    const range = first === last ? String(first) : first + "–" + last;
+    return "| " + chapter + " | " + range + " | " + chapterLessons.length + " |";
+  });
+  const lessonSections = groups.flatMap(({ chapter, lessons: chapterLessons }) => [
+    "### " + chapter,
+    "",
+    "| Lesson | Problem-oriented title | Main learning outcome | Live anchor(s) | Slides | Demo | Target |",
+    "| ---: | --- | --- | --- | ---: | ---: | ---: |",
+    ...chapterLessons.map((lesson) => {
+      const lessonNo = String(lesson.number).padStart(2, "0");
+      const demos = lesson.experiments.map((item) => item.id).join(", ");
+      return "| [" + lessonNo + "](lesson-" + lessonNo + ".md) | " + lesson.title + " | " + lesson.subtitle + " | " + demos + " | " + plannedSlideCount(lesson) + " | " + demoMinutes(lesson) + " min | " + lessonDuration(lesson) + " min |";
+    }),
+    ""
+  ]);
+  return [
+    "# AI Agents in Depth — English Video Course",
+    "",
+    "Approved Option B curriculum: 42 problem-oriented lessons following the English book order. Each lesson is 15–20 minutes, budgeting approximately one minute per Slidev slide plus one to three minutes per live experiment.",
+    "",
+    "## Learning arc",
+    "",
+    "| Movement | Chapters | Viewer progression |",
+    "| --- | --- | --- |",
+    "| Build an Agent | Introduction–Chapter 5 | Context → memory → tools → executable capabilities |",
+    "| Improve it scientifically | Chapters 6–8 | Evaluation → post-training → continual evolution |",
+    "| Expand it | Chapters 9–10 | Voice → Computer Use → robotics → multi-Agent collaboration |",
+    "",
+    "## Approved chapter allocation",
+    "",
+    "| Book section | Lessons | Count |",
+    "| --- | ---: | ---: |",
+    ...allocationRows,
+    "| **Total** | **1–42** | **42** |",
+    "",
+    "Chapter 7 intentionally receives six lessons because post-training and reinforcement learning are the largest conceptual jump for viewers without prior ML-training knowledge. Chapter 9 receives four lessons so Computer Use and robotics have separate mechanisms, experiments, and safety boundaries.",
+    "",
+    "## Lesson-by-lesson outline",
+    "",
+    ...lessonSections,
+    "",
+    "## Recording contract",
+    "",
+    "- Speak in your own voice and add interpretation; the decks are visual prompts, not narration scripts.",
+    "- Run the listed commands in one contiguous terminal block after the explicit handoff slide.",
+    "- Treat preflights, validators, smoke checks, and dry configurations as scoped evidence—not completed long campaigns.",
+    "- Use the linked companion projects for experiments that are not demonstrated live.",
+    "- Demo-heavy lessons combine or remove conceptual slides so slide time plus terminal time stays within 20 minutes.",
+    ""
+  ].join("\n");
+}
+
+async function main() {
+  if (lessons.length !== 42) fail("Expected exactly 42 lessons; found " + lessons.length);
+  lessons.forEach(validateLesson);
+
+  const allocation = new Map();
+  for (const lesson of lessons) allocation.set(lesson.chapter, (allocation.get(lesson.chapter) || 0) + 1);
+  const expectedAllocation = new Map([
+    ["Introduction", 1], ["Chapter 1", 3], ["Chapter 2", 5], ["Chapter 3", 4],
+    ["Chapter 4", 4], ["Chapter 5", 4], ["Chapter 6", 4], ["Chapter 7", 6],
+    ["Chapter 8", 3], ["Chapter 9", 4], ["Chapter 10", 4]
+  ]);
+  if (JSON.stringify([...allocation]) !== JSON.stringify([...expectedAllocation])) {
+    fail("Lesson allocation does not match approved Option B");
+  }
+
+  const bookText = (await Promise.all(Array.from({ length: 10 }, (_, index) =>
+    readFile(path.join(REPO, "book-en", "chapter" + (index + 1) + ".md"), "utf8")
+  ))).join("\n");
+  const experimentIds = [...new Set([...bookText.matchAll(/Experiment\s+(\d+-\d+)/g)].map((match) => match[1]))];
+  const courseText = JSON.stringify(lessons);
+  const missingExperiments = experimentIds.filter((id) => !courseText.includes(id));
+  if (missingExperiments.length) fail("Unlinked book experiments: " + missingExperiments.join(", "));
+
+  await mkdir(PUBLIC_IMAGES, { recursive: true });
+  const selection = selectedLessonNumbers();
+  const targetLessons = selection
+    ? lessons.filter((lesson) => selection.has(lesson.number))
+    : lessons;
+  if (selection && targetLessons.length !== selection.size) fail("Could not resolve every requested lesson");
+
+  const figures = new Set([...lessons.map((lesson) => lesson.figure), ...chapter1PilotFigures]);
+  for (const figure of figures) {
+    const source = await readFile(path.join(REPO, "book-en", "images", figure), "utf8");
+    if (CJK.test(source)) fail("Selected figure contains non-English visible text: " + figure);
+  }
+  await Promise.all([...figures].map((figure) => copyFile(
+    path.join(REPO, "book-en", "images", figure),
+    path.join(PUBLIC_IMAGES, figure)
+  )));
+  if (!selection) {
+    const staleFigures = (await readdir(PUBLIC_IMAGES))
+      .filter((figure) => figure.endsWith(".svg") && !figures.has(figure))
+      .map((figure) => path.join(PUBLIC_IMAGES, figure));
+    await Promise.all(staleFigures.map((figure) => rm(figure)));
+  }
+
+  const expectedDecks = new Set();
+  let totalSlides = 0;
+  for (const lesson of targetLessons) {
+    const lessonNo = String(lesson.number).padStart(2, "0");
+    const name = "lesson-" + lessonNo + ".md";
+    expectedDecks.add(name);
+    const rendered = renderChapter1Pilot(lesson) ?? renderLesson(lesson);
+    if (rendered.slideCount !== plannedSlideCount(lesson)) {
+      fail("Lesson " + lesson.number + " rendered " + rendered.slideCount + " slides; planned " + plannedSlideCount(lesson));
+    }
+    if ((rendered.markdown.match(/Switching to the terminal/g) || []).length !== 1) {
+      fail("Lesson " + lesson.number + " must contain exactly one terminal handoff");
+    }
+    totalSlides += rendered.slideCount;
+    await writeFile(path.join(HERE, name), rendered.markdown, "utf8");
+  }
+
+  if (!selection) {
+    const stale = [];
+    for (let number = 43; number <= 99; number += 1) {
+      const name = "lesson-" + String(number).padStart(2, "0") + ".md";
+      const target = path.join(HERE, name);
+      if (existsSync(target) && !expectedDecks.has(name)) stale.push(target);
+    }
+    await Promise.all(stale.map((target) => rm(target)));
+    await writeFile(path.join(HERE, "COURSE_OUTLINE.md"), outline(), "utf8");
+  }
+
+  const scope = selection ? targetLessons.length + " selected Slidev decks" : "42 Slidev decks";
+  const outlineStatus = selection ? "without changing COURSE_OUTLINE.md" : "with COURSE_OUTLINE.md";
+  console.log("Generated " + scope + " (" + totalSlides + " slides), " + outlineStatus + ", and synchronized " + figures.size + " figure assets.");
+}
+
+await main();