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open-design/design-templates/html-ppt-course-module/example.html
Tom Huang b5eb8c1647
feat: generic skills + split skills/design-templates + finalize-design API (#955) 
* feat: general-purpose skills with @-mention composition and user import

Lift skills from "one mode-bound skill per project" to a generic capability
the user can compose per turn:

- Daemon: scan multiple skill roots (user-skills under runtime data, then
  the bundled `skills/`); user-imported skills can shadow built-ins by id.
- New `POST /api/skills/import` and `DELETE /api/skills/:id` endpoints,
  with CONFLICT/BAD_REQUEST/NOT_FOUND error codes and built-in delete
  protection.
- ChatRequest gains `skillIds: string[]`; the chat run concatenates each
  picked skill's body (and merges craftRequires) into the system prompt
  for that turn only — the project's persistent `skillId` is untouched.
- Web composer: `@` popover now lists skills alongside project files;
  picks render as removable chips above the textarea and ride along with
  the request as `skillIds`.
- Settings → Library: import form (name/description/triggers/body),
  per-card delete for user skills, "user" origin badge.

* chore(web): drop welcome pet teaser + add ds→prompt-template mapping util

- SettingsDialog: remove the inline pet adoption teaser from the welcome
  panel so the first-run modal stays focused on configuration.
- New `inferPromptTemplateCategoriesForDs(ds)` helper that maps a design
  system's authored metadata to prompt-template gallery categories.
  Imported by the design-system gallery wiring on a sibling branch; no
  callers in this branch yet.

* feat: split skills/design-templates and add finalize-design API

Phase 0 of the skills/design-templates refactor (specs/current/
skills-and-design-templates.md):

- Move ~104 rendering catalogue entries from skills/ to design-templates/
  and keep skills/ for the small set of functional skills that *do work*
  on user input (utilities, briefs, packagers).
- Add design-templates/AGENTS.md and skills/AGENTS.md describing the
  contract, and a brand-agnostic craft/ surface for opt-in craft rules.
- Daemon: add DESIGN_TEMPLATES_DIR / USER_DESIGN_TEMPLATES_DIR roots and
  an /api/design-templates surface mirroring /api/skills. Asset/example
  routes still span both registries so existing srcdoc URLs keep
  resolving across the rename.
- Web: split LibrarySection into SkillsSection + DesignSystemsSection,
  rename the EntryView "Examples" tab to "Templates", and update locales
  + the New-project picker accordingly.

Adds the finalize-design endpoint:

- New apps/daemon/src/finalize-design.ts and packages/contracts/src/api/
  finalize.ts — one-shot synthesis of a project's transcript + active
  design system + current artifact into <projectDir>/DESIGN.md via the
  Anthropic Messages API. Per-project .finalize.lock mirrors the
  transcript-export hygiene from PR #493; provider credentials are not
  persisted by the daemon.

Other supporting changes:

- README + AGENTS.md updates to document the new directory split and
  craft/ surface, plus i18n strings across 13 locales.
- Test refactors and new coverage (finalize-design, runs, sidecar
  server, plus refreshed daemon integration tests).
- .gitignore: scope the *.exe ignore to /OpenDesign.exe so legitimate
  vendor binaries are no longer hidden.

* fix(merge): move clinical-case-report to design-templates/

Origin/main added the clinical-case-report skill under skills/ before
the skills/design-templates split landed. Its od.mode is prototype, so
per specs/current/skills-and-design-templates.md it is a design template
and belongs alongside the other rendering catalogue entries — not under
the slimmed-down functional skills/ root. Moving it keeps the EntryView
Templates tab consistent with origin/main's intent.

* feat(skills): curated design/creative catalogue + collapsible Settings rows

Seed ~100 curated design/creative skill stubs under skills/ sourced from
awesome-claude-skills (ComposioHQ) and awesome-agent-skills (VoltAgent).
Each stub carries an od.category tag so the new filter pill row in
Settings -> Skills can group them. The seed script
(scripts/seed-curated-design-skills.ts, pnpm seed:curated-design-skills)
is idempotent: it only creates folders that don't already exist, so
hand-edited stubs are never overwritten.

- Daemon: parse and surface od.category on SkillInfo with a strict slug
  normaliser; mirror the field on SkillSummary in @open-design/contracts.
  Category is purely a UI hint — system-prompt composition is unchanged.
- Web: rewrite SkillsSection from a left-list / right-detail grid into a
  vertical stack of collapsible rows mirroring the External MCP panel
  (header always visible with name + mode/source/category pills + per-row
  enable toggle; SKILL.md preview, file tree and inline edit form expand
  on demand). Add a Category filter row above the list. Reorder Settings
  nav so Skills + External MCP sit above the Composio/MCP cluster. Update
  composer placeholder/hint across 17 locales to advertise '@ files or
  skills · / for commands'.
- Docs: extend skills/AGENTS.md with the curated catalogue rules
  (idempotency, category vocabulary, no upstream vendoring).

Co-authored-by: Cursor <cursoragent@cursor.com>

* test(skills): teach localized-content + system-prompt tests about the skills/design-templates split

mrcfps blocking review on PR #955: the skills/design-templates split
(b5993385) moved ~110 SKILL.md entries out of `skills/` and into
`design-templates/`, but two repo-level tests still hard-coded the
single-root layout, so CI gates went red on the merged branch:

- `e2e/tests/localized-content.test.ts` only scanned `<repo>/skills`
  while the locale `skillCopy` map keeps id-keyed entries spanning
  both roots (ExamplesTab/Templates uses one lookup regardless of
  origin). Teach the helper to read both `skills/` and
  `design-templates/`, deduplicating ids so the union matches the
  localized claim.
- `apps/daemon/tests/prompts/system.test.ts` read
  `skills/live-artifact/SKILL.md`, which now lives under
  `design-templates/live-artifact/`. Update the absolute path so
  composeSystemPrompt's coverage of the live-artifact preamble is
  exercised again.

Also enroll the curated design/creative catalogue (PR #955, ~91
stubs sourced from awesome-claude-skills / awesome-agent-skills) in
the DE / FR / RU `_SKILL_IDS_WITH_EN_FALLBACK` lists. The stubs are
English-only by design (frontmatter advertises an upstream URL); the
fallback list is exactly the place to acknowledge "we know this id
exists, English copy is fine here" so the localized-content coverage
gate passes without forcing a translation task per locale.

Co-authored-by: Cursor <cursoragent@cursor.com>

* fix(skills): always quote frontmatter name so importUserSkill round-trips numeric / boolean ids

mrcfps PR #955 review: `buildSkillMarkdown` emitted `name:
${escapeYamlString(name)}` without quotes, so YAML coerced names
like `123`, `true`, `false`, or `null` into non-string scalars on
re-parse. listSkills() then read `data.name` as a number/boolean
and the import flow's follow-up `findSkillById(skills, result.id)`
missed it, falling into `/api/skills/import`'s "imported skill
could not be re-read" 500 path for those ids.

Switch the emitter to a quoted scalar (`name: "..."`) — the
double-escape already in `escapeYamlString` makes the quoted form
safe — and add a round-trip test covering `123`, `true`, `false`,
`null`, and `0` to lock in the contract.

Co-authored-by: Cursor <cursoragent@cursor.com>

* fix(web): drop staged-skill chips when the matching @<id> token leaves the draft

mrcfps PR #955 review: `submit()` always forwarded every id in
`stagedSkills`, but that state was only mutated on picker click and
chip removal. Hand-deleting an `@<id>` token from the textarea left
the chip staged, so the request still carried `skillIds: [<id>]` and
the daemon composed a skill the prompt no longer referenced.

Sync the chips with the draft inside `handleChange()` by pruning
`stagedSkills` whenever the new value no longer contains the
`@<id>` token (using the same whitespace boundary as
`removeStagedSkill`'s strip regex). Comment explains why this
prune does not run for `staged` file attachments — users frequently
add files via the upload button without leaving an `@<path>` token,
so a symmetric prune there would erase legitimate uploads.

Co-authored-by: Cursor <cursoragent@cursor.com>

* fix(daemon): stage @-composed skills' side files alongside the active skill

codex PR #955 review: composing a per-turn `@`-picked skill into the
system prompt appended its body (with the `withSkillRootPreamble`
guidance pointing at relative paths under `<cwd>/.od-skills/<folder>/`)
but never staged the actual folder. `startChatRun` only copied
`activeSkillDir`, so when the project's primary skill was different
(or absent) the composed skill's references/, examples/, and scripts/
files lived only at their absolute repo path — agents that honour
the cwd-relative form (or that don't get `--add-dir`, e.g. Codex with
allowlisted gpt-image projects) couldn't reach them.

Thread the composed skills' dirs out of `composeDaemonSystemPrompt`
as `extraSkillDirs` and stage each one through the same
`stageActiveSkill` API used for the primary skill. Dedupe by folder
basename so a project whose primary skill is also `@`-composed isn't
copied twice. Each preamble already advertises its own folder, so the
prompt and the staged tree stay aligned without further changes.

Co-authored-by: Cursor <cursoragent@cursor.com>

* fix(web): respect the Library disable toggle in the project @-mention picker

codex PR #955 review: only `EntryView` received `enabledSkills`
(filtered against `config.disabledSkills`); active projects still
got `skills={skills}` raw, so a skill the user disabled in Settings
kept appearing in the project's `@`-mention popover and could ride
along to the daemon via `skillIds`. That broke the Library toggle
for any project opened on the post-split branch.

Compute a functional-skills-only enabled subset
(`enabledFunctionalSkills`) and pass it into `<ProjectView>` instead.
Templates stay separate — design-templates are filtered through their
own `enabledDesignTemplates` memo for the Templates gallery — so
ProjectView's chat composer still only sees skills, never templates,
matching the pre-split prop surface.

Co-authored-by: Cursor <cursoragent@cursor.com>

* test(e2e): mock /api/design-templates for example-use-prompt flow

The Templates tab in EntryView fetches from /api/design-templates after
the skills/design-templates split (specs/current/skills-and-design-templates.md).
The example-use-prompt Playwright scenario only mocked /api/skills, so the
gallery card never appeared and the test timed out waiting on
example-card-warm-utility-example. Serve the same fixture summary on both
endpoints so the templates gallery renders the card the test clicks.

Co-authored-by: Cursor <cursoragent@cursor.com>

* test(tools-pack): create design-templates fixture for resources test

The packaging resources copy now bundles the new design-templates tree
alongside skills (see resources.ts BUNDLED_RESOURCE_TREES). The
copyBundledResourceTrees fixture only created skills, design-systems,
craft, etc., so the recursive copy crashed with ENOENT on
design-templates before it could check the prompt-templates assertion.
Add the missing fixture directory so the test exercises the same set
of resource trees the packaged build does.

Co-authored-by: Cursor <cursoragent@cursor.com>

* fix(skills): clone built-in side files into the shadow on first edit

mrcfps PR #955 review: editing a built-in skill wrote a USER_SKILLS_DIR
shadow folder that contained only a new SKILL.md. The next listSkills()
pass surfaced the shadow as the active dir, but every side-file resolver
(/api/skills/:id/files, /example, /assets/*, the system-prompt preamble,
and the per-turn cwd staging) reads through skill.dir. With nothing but
SKILL.md in the shadow, the bundled assets/, references/, scripts/, and
examples/ disappeared the moment the user hit save — a built-in like
last30days or live-artifact would break immediately after edit instead
of just having its body overridden.

Teach updateUserSkill() to take a `sourceDir` and clone every entry
except SKILL.md / dotfiles into the shadow on the very first edit. The
shadow stays self-contained, so all the resolvers keep working without
fallback bookkeeping. Subsequent edits detect the existing shadow and
skip the clone, so user tweaks under the side tree survive a re-save.

Wire `sourceDir: skill.dir` from server.ts's PUT /api/skills/:id handler
and add two regression tests:
- 'clones built-in side files into the shadow on the first edit' walks
  the file tree after save and asserts assets/template.html, references/
  notes.md, and scripts/helper.sh all round-trip from the built-in.
- 'preserves user-edited side files on subsequent edits' edits the
  staged assets/template.html, re-saves, and confirms the user content
  is still there.

Co-authored-by: Cursor <cursoragent@cursor.com>

* test(e2e): rename home tab from Examples to Templates

The Examples tab was renamed to Templates in EntryView (b5993385's
skills/design-templates split — entry.tabExamples became entry.tabTemplates
and the tab value moved from 'examples' to 'templates'), but
entry-chrome-flows still asserted the old label and testId. Update both.

* fix(skills+web): preserve template body in API mode and dir-based skill delete

Two follow-ups from PR #955 review:

1. ProjectView only received `enabledFunctionalSkills`, but
   `composedSystemPrompt()` still resolved `project.skillId` through that
   prop and `fetchSkill()`. Projects created from the new
   `/api/design-templates` surface keep a template id in `project.skillId`,
   so opening one in API mode dropped the template body from the system
   prompt and the upstream request ran without the project's primary
   template instructions. Now ProjectView takes a separate
   `designTemplates` prop (the unfiltered template list, so a
   later-disabled template still loads for projects already created from
   it) and `composedSystemPrompt()` plus the metadata / `isDeck` lookups
   fall back to that list, with `fetchDesignTemplate()` as the body-fetch
   fallback to `fetchSkill()`. The chat composer's `@`-picker keeps
   receiving only the enabled functional skills.

2. `DELETE /api/skills/:id` used `deleteUserSkill(USER_SKILLS_DIR, skill.id)`
   which re-slugified the frontmatter id and removed
   `<userSkillsDir>/<slug>/`. That matched the import shape but missed the
   install shape — `installFromTarget` writes the folder at
   `sanitizeRepoName(url)` (GitHub) or `path.basename(realpath)` (local
   symlink), neither of which is guaranteed to equal the slugified
   frontmatter `name`. A duplicate `app.delete('/api/skills/:id', ...)`
   handler at the install routes never fired because Express resolved the
   earlier registration first, leaving the install/uninstall path without
   working teardown. The handler now removes `skill.dir` (the absolute
   path listSkills already discovered) under a USER_SKILLS_DIR safety
   check, using `lstat` + `unlinkSync` so symlinked local installs unlink
   cleanly without recursing into the user's source tree. The dead
   duplicate handler is removed; `deleteUserSkill` is dropped from the
   server.ts import set (still exported and unit-tested in skills.ts).
   Regression coverage in `apps/daemon/tests/skills-delete-route.test.ts`
   pins both shapes plus the symlink-preserves-source case.

* test(daemon): point hyperframes system-prompt test at design-templates

The merge with main brought in a hyperframes system-prompt test that
reads `skills/hyperframes/SKILL.md`, but this branch's split moved
`hyperframes` into `design-templates/` (same migration as `live-artifact`
already handled above in this file). CI was failing with ENOENT on the
old path.

---------

Co-authored-by: Cursor <cursoragent@cursor.com>
2026-05-11 17:48:34 +08:00

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<title>Module 04 · Recursion · CS101</title>
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</style></head>
<body class="tpl-course-module">
<div class="deck">
<!-- 1. Cover -->
<section class="slide full" data-title="Cover">
<p class="kicker">CS 101 · MODULE 04</p>
<h1 class="h1 mt-s">Recursion: solving<br>problems by <em>calling yourself</em>.</h1>
<p class="lede mt-l" style="max-width:62ch">In this module you'll learn why a function that calls itself is not a trick, but the most natural way to describe problems that contain smaller copies of themselves.</p>
<div class="row mt-l" style="gap:16px">
<span class="pill-academic">~ 45 min read</span>
<span class="pill-academic">prereq · functions, if/else</span>
<span class="pill-academic">lang · Python</span>
</div>
<div class="deck-footer"><span>Dr. A. Rivera · Spring 2026</span><span class="slide-number" data-current="1" data-total="7"></span></div>
</section>
<!-- 2. Objectives -->
<section class="slide" data-title="Objectives">
<aside class="sidebar">
<div class="brand">CS 101 · M04</div>
<h5>Learning objectives</h5>
<ul class="obj-list">
<li class="current">Define recursion</li>
<li>Identify a base case</li>
<li>Trace a recursive call</li>
<li>Convert loop ↔ recursion</li>
<li>Recognize when recursion helps</li>
</ul>
<h5>Module progress</h5>
<p class="dim" style="font-size:13px">Page 2 of 7 · ~5 min in</p>
</aside>
<div class="main">
<p class="kicker">OBJECTIVES</p>
<h2 class="h2 mt-s">By the end, you will be able to…</h2>
<div class="stack mt-l">
<div class="concept-box"><h4>① Explain recursion in one sentence.</h4><p class="dim">"A function that solves a problem by calling itself on a smaller version of that problem."</p></div>
<div class="concept-box"><h4>② Write a base case that always terminates.</h4><p class="dim">Every recursive function must have an exit door, or it runs forever.</p></div>
<div class="concept-box"><h4>③ Trace a call stack on paper.</h4><p class="dim">Given <code>fact(4)</code>, draw the stack frames top-to-bottom.</p></div>
<div class="concept-box"><h4>④ Convert a while-loop to a recursive equivalent.</h4><p class="dim">And explain when one is clearer than the other.</p></div>
</div>
</div>
</section>
<!-- 3. Concept -->
<section class="slide" data-title="Concept">
<aside class="sidebar">
<div class="brand">CS 101 · M04</div>
<h5>Learning objectives</h5>
<ul class="obj-list">
<li class="done">Define recursion</li>
<li class="current">Identify a base case</li>
<li>Trace a recursive call</li>
<li>Convert loop ↔ recursion</li>
<li>Recognize when recursion helps</li>
</ul>
<h5>Key terms</h5>
<p class="dim" style="font-size:13px">base case · recursive case · call stack · tail call</p>
</aside>
<div class="main">
<p class="kicker">CORE CONCEPT</p>
<h2 class="h2 mt-s">Two parts, always.</h2>
<p class="lede mt-m">A recursive function has exactly two things inside it: a <b>base case</b> (when to stop) and a <b>recursive case</b> (how to shrink the problem before calling yourself).</p>
<div class="callout">
<b>Rule of thumb.</b> If you can't name the base case out loud, don't write the recursion yet. Draw it on paper first.
</div>
<div class="grid g2 mt-l">
<div class="concept-box"><h4>Base case</h4><p class="dim">The smallest possible input — one the function answers directly, without calling itself.</p><p class="pill-academic">e.g. <b>n == 0</b></p></div>
<div class="concept-box"><h4>Recursive case</h4><p class="dim">Every other input — delegate to a smaller version of the same problem.</p><p class="pill-academic">e.g. <b>n × fact(n-1)</b></p></div>
</div>
</div>
</section>
<!-- 4. Example -->
<section class="slide" data-title="Example">
<aside class="sidebar">
<div class="brand">CS 101 · M04</div>
<h5>Learning objectives</h5>
<ul class="obj-list">
<li class="done">Define recursion</li>
<li class="done">Identify a base case</li>
<li class="current">Trace a recursive call</li>
<li>Convert loop ↔ recursion</li>
<li>Recognize when recursion helps</li>
</ul>
<h5>Try it yourself</h5>
<p class="dim" style="font-size:13px">Open repl.it and run the code on the right. Then try <code>fact(10)</code>.</p>
</aside>
<div class="main">
<p class="kicker">WORKED EXAMPLE</p>
<h2 class="h2 mt-s">Factorial, 7 lines.</h2>
<div class="code mt-m"><pre style="margin:0"><span class="cmt"># fact(n) = n × (n-1) × … × 1, and fact(0) = 1</span>
<span class="kw">def</span> fact(n):
<span class="kw">if</span> n == <span class="str">0</span>: <span class="cmt"># base case</span>
<span class="kw">return</span> <span class="str">1</span>
<span class="kw">return</span> n * fact(n - <span class="str">1</span>) <span class="cmt"># recursive case</span>
<span class="kw">print</span>(fact(<span class="str">4</span>)) <span class="cmt"># → 24</span></pre></div>
<div class="callout">
<b>Trace fact(4).</b> 4 × fact(3) → 4 × (3 × fact(2)) → 4 × 3 × (2 × fact(1)) → 4 × 3 × 2 × 1 × fact(0) → 4 × 3 × 2 × 1 × 1 = <b>24</b>.
</div>
</div>
</section>
<!-- 5. Exercise -->
<section class="slide" data-title="Exercise">
<aside class="sidebar">
<div class="brand">CS 101 · M04</div>
<h5>Learning objectives</h5>
<ul class="obj-list">
<li class="done">Define recursion</li>
<li class="done">Identify a base case</li>
<li class="done">Trace a recursive call</li>
<li class="current">Convert loop ↔ recursion</li>
<li>Recognize when recursion helps</li>
</ul>
<h5>Time</h5>
<p class="dim" style="font-size:13px">~10 minutes · solo</p>
</aside>
<div class="main">
<p class="kicker">EXERCISE 4.1</p>
<h2 class="h2 mt-s">Write <em>sum_to(n)</em>.</h2>
<p class="lede mt-m">Return <code>1 + 2 + … + n</code> using recursion — no loops allowed.</p>
<div class="exercise mt-l">
<p style="margin:0;font-size:18px;color:var(--text-1)"><b>Your task</b></p>
<ol style="color:var(--text-2);line-height:1.8;margin:10px 0 0">
<li>Write the base case. What does <code>sum_to(0)</code> return?</li>
<li>Write the recursive case in terms of <code>sum_to(n - 1)</code>.</li>
<li>Test it: <code>sum_to(5) == 15</code>, <code>sum_to(10) == 55</code>.</li>
<li>Bonus: what happens if you call <code>sum_to(-3)</code>? Fix it.</li>
</ol>
</div>
<p class="dim mt-m" style="font-size:14px">Stuck? Remember: a base case is the smallest input you already know the answer to.</p>
</div>
</section>
<!-- 6. Check understanding -->
<section class="slide" data-title="Check">
<aside class="sidebar">
<div class="brand">CS 101 · M04</div>
<h5>Learning objectives</h5>
<ul class="obj-list">
<li class="done">Define recursion</li>
<li class="done">Identify a base case</li>
<li class="done">Trace a recursive call</li>
<li class="done">Convert loop ↔ recursion</li>
<li class="current">Recognize when recursion helps</li>
</ul>
<h5>Self-assess</h5>
<p class="dim" style="font-size:13px">You should get 3/3.</p>
</aside>
<div class="main">
<p class="kicker">CHECK YOUR UNDERSTANDING</p>
<h2 class="h2 mt-s">Which function will recurse forever?</h2>
<div class="mt-l">
<div class="mcq"><div class="letter">A</div><div><b>def f(n): return 1 if n == 0 else n * f(n - 1)</b><p class="dim" style="font-size:13px;margin:4px 0 0">Base case <code>n == 0</code>, shrinks toward it. Terminates.</p></div></div>
<div class="mcq correct"><div class="letter">B</div><div><b>def f(n): return n + f(n + 1)</b><p class="dim" style="font-size:13px;margin:4px 0 0"><b style="color:var(--accent)">✓ Correct.</b> No base case, and <code>n</code> grows — infinite recursion.</p></div></div>
<div class="mcq"><div class="letter">C</div><div><b>def f(n): return n if n &lt; 2 else f(n - 1) + f(n - 2)</b><p class="dim" style="font-size:13px;margin:4px 0 0">Classic Fibonacci. Base case on <code>n &lt; 2</code>. Terminates.</p></div></div>
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<p class="kicker">SUMMARY · MODULE 04</p>
<h1 class="h1 mt-s">You can now…</h1>
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<div class="concept-box"><h4>✓ Define recursion</h4><p class="dim">A function that calls itself on a smaller input.</p></div>
<div class="concept-box"><h4>✓ Write a safe base case</h4><p class="dim">Every recursion needs an exit door.</p></div>
<div class="concept-box"><h4>✓ Trace a call stack</h4><p class="dim">You can unwind <code>fact(4)</code> by hand.</p></div>
<div class="concept-box"><h4>✓ Judge when to use it</h4><p class="dim">Trees and self-similar problems → recursion. Flat iteration → loop.</p></div>
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<b>Up next · Module 05.</b> Divide &amp; conquer: merge sort. We'll use everything you just learned — but on lists, not numbers.
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