changelog-video

Turns a written list of weekly updates into a short finished video with narration and graphics.

Installation
Run `npx skills add "https://github.com/heygen-com/hyperframes" --skill "changelog-video"` to install this skill, then follow its SKILL.md instructions for my next request.

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SKILL.mdShow the author's original SKILL.md
---
name: changelog-video
description: Turn a weekly changelog .md into a finished branded changelog video (square 1080, ~45-60s, Annie VO, animated brand background, mock-UI visualizations, lowkey captions). Use when the user provides a changelog/digest markdown and wants the weekly video, or says "changelog video". Self-contained — fonts, background, lexicon, and scripts ship in this skill.
---

# Changelog → Branded Video

Input: a changelog .md (themes + items, like the weekly HyperFrames digest).
Output: a lint-clean, seam-gate-green HyperFrames project in
`projects/active/weekly-changelog-<range>/`. Render only when asked.

**Load first, non-negotiable:** `motion-doctrine` (+ `cut-the-curve`,
`oversized-cursor` if a cursor appears, `seam-craft`) and `captions-overlay`.
This skill supplies the changelog-specific pipeline; the doctrine supplies the
motion law.

## The prime directive: visualize, don't list

Every theme is illustrated by an **animated mock of the actual UI or a
faithful analog** acting out the change in experience — never text bullets.
Route every theme/item through `references/visualization-registry.md` BEFORE
writing the script; the registry decides ui-recreate / ui-analog / terminal /
checklist. Text checklist is the LAST resort, reserved for genuinely
non-visual items (reliability fix lists).

## Pipeline

### 0 · Bootstrap the project from THIS skill's assets — non-negotiable

**Do this before writing any composition HTML. Skipping it always produces a video that looks like a similar project you built before, NOT this skill's brand — that's the single most common way this skill goes off-brand.** The skill's assets, fonts, and scaffold are the skill; the SKILL.md prompt is a router.

```bash
mkdir -p project/assets/fonts
cp <SKILL_DIR>/assets/fonts/*.woff2 project/assets/fonts/
cp <SKILL_DIR>/assets/bgm.mp3 project/bgm.mp3
ffmpeg -y -stream_loop 15 -i <SKILL_DIR>/assets/bg-pattern.mp4 -t <TOTAL> \
  -vf "scale=1080:1080,fps=30,eq=saturation=0.72,drawbox=c=black@0.5:t=fill" \
  -an -c:v libx264 -crf 20 -pix_fmt yuv420p project/assets/bg-pattern-<TOTAL>s.mp4
cp <SKILL_DIR>/examples/master-skeleton.html project/index.html
```

Then **read `references/build-spec.md` end-to-end** (not skimmed) — it defines the brand tokens (TT Norms Pro + ABC Solar Display + TT Norms Mono, cream `#f5f6f4`, rationed green `#5ef17c`, glass cards with green-tinted borders, kicker/sec-chip pill shape, 32px caption rail at `top: 990`) that every scene inherits from the scaffold.

Only THEN begin steps 1-6 below. Steps 1-4 (parse, route, script, VO) plan what goes into the scaffold; step 5 fills placeholders (`<RANGE>`, `<TOTAL>`, `<CUT_N>`, `<DUR_N>`, scene bodies) inside the already-copied `project/index.html` — you do NOT rewrite the scaffold's chrome, fonts, palette, or layout shell.

If you catch yourself reaching for `cp` on a prior video's `index.html`, or writing your own `@font-face` declarations, or designing a WebGL shader background instead of using the encoded bg-pattern MP4 above: STOP. Delete the current `index.html` and restart at the `cp` of the master-skeleton scaffold. Rebuilding scene content on the right scaffold is cheaper than retrofitting brand into the wrong scaffold.

### 1 · Parse + editorial cut

- Extract: week range, headline stats (releases, commits), themes, items.
- **Budget: 45-60s total.** Title ≤2s, outro ≤3.5s, 4 themes ≈ 9-12s each.
- Per theme keep ONE hero visualization + at most 3 spoken items. Everything
  else exists only as the outro's "full digest" pointer. Cutting is the job:
  a changelog with 30 items still yields ≤14 spoken beats.
- Order themes by story: marquee feature → product surface → performance →
  reliability (the digest usually already reads this way).

### 2 · Visualization routing

For each theme, pick the surface from `references/visualization-registry.md`
and write one line: `theme → surface → the 2-4 sequenced actions the mock
performs, each tied to a script phrase`. If no registry surface fits and no
faithful analog exists, it's a checklist scene — don't invent fake UI for
something we can't represent honestly.

### 3 · Two-layer script (spoken vs display)

Write the script as **token lines** per `references/script-voice.md`:
conversational register, every technical term carrying a `spoken` phonetic
form from `references/lexicon.json` while `display` keeps standard spelling.
Captions show `display`; the VO reads `spoken`. Any term not in the lexicon:
STOP and ask the user how it's pronounced, then add it to the lexicon.
Save as `script-tokens.json` in the project.

### 4 · VO — Annie (HeyGen, pinned)

```bash
# spoken-layer text only; words JSON = ground-truth timestamps of the SPOKEN text
# Repo-native path: the changelog-video skill runs from the hyperframes repo root,
# so it uses the tracked hyperframes-media TTS helper directly (no `npx hyperframes
# skills` install step). If you've copied the skill into another repo, swap in
# your own path to the media-use / hyperframes-media heygen-tts.mjs.
node skills/hyperframes-media/scripts/heygen-tts.mjs ./vo-spoken.txt \
  -o voiceover.mp3 --words vo-words.json \
  --voice 330290724a1b470fb63153f34d4c0183   # Annie — lifelike (do not substitute)
```

Requires `heygen` CLI ≥0.3.0 authenticated (`heygen auth login --oauth`).
Then align spoken timestamps back to display tokens:

```bash
node <SKILL_DIR>/scripts/align-captions.mjs \
  --tokens script-tokens.json --words vo-words.json --out captions.json
```

`captions.json` is the caption-rail input (display spelling, spoken timing).
The aligner prints `MISMATCH` warnings — resolve every one before building
(usually a lexicon spelling the TTS renders as multiple words). **The audio
is the clock**: all beat times come from `vo-words.json`; a VO regen re-opens
every seam.

**Word-timings are a hard gate.** Before moving on to step 5, verify
`vo-words.json` is non-empty and has a `words: [...]` array with `start`/`end`
per word. If it's empty (0 bytes) or missing the array — a known failure mode
when the TTS provider returns audio but no timestamp payload — DO NOT proceed
without them. Fallback: forced-align the produced audio against the display
script using local whisper:

```bash
uvx --from openai-whisper whisper voiceover.mp3 \
  --model base.en --language en --word_timestamps True \
  --output_format json --output_dir .
# then run align-captions.mjs with --words voiceover.json (same shape)
```

Whisper mishears TTS renderings ("gee-sap" → "gsap", "heyjen" → "hey Jen",
etc.) — captions still use the DISPLAY spelling from `script-tokens.json`;
whisper only supplies the timestamps. `align-captions.mjs` handles the join.
This fallback is the difference between a captioned build and a silently
uncaptioned one.

### 5 · Build

Follow `references/build-spec.md` exactly: brand tokens + fonts (bundled in
`<SKILL_DIR>/assets/`), the animated background encode, scene scaffold,
chrome, caption rail, one rationed green moment per scene. Then the doctrine
order: `ledger.json` (all ordinary seams cut-the-curve LEFT) → seam-stamp →
internal beats on VO words → seam-gate verify.

**Captions are non-optional.** The master-skeleton ships a caption-rail IIFE
that reads a `LINES` array — leaving that array empty is a shipped bug, not a
style choice. Populate it from `captions.json` before proceeding to step 6:

```javascript
// paste in place of "const LINES = /* … */ []" in the caption-rail IIFE:
const LINES = /* contents of captions.json */ [
  { id: 0, end: 2.74, w: [["This", 0.0], ["week,", 0.30], …] },
  …
];
```

If `align-captions.mjs` was skipped or `LINES` is `[]`, the frame check in
step 6 will fail — do not paper over it by removing `#cap-line` from the
scaffold.

### 6 · Gates (all green before presenting)

1. `bun run --cwd packages/cli hyperframes check --caption-zone "x0=0;y0=.90;x1=1;y1=1;severity=error;seek=.02,.06,.10,.14,.18,.22,.26,.30,.34,.38,.42,.46,.50,.54,.58,.62,.66,.70,.74,.78,.82,.86,.90,.94,.98"` (or the installed
   `hyperframes` CLI from the repo-local `skills/hyperframes-cli/` skill) —
   0 errors (contrast: dim text ≥ .66 alpha; scene content stays above the
   caption rail). Do NOT reach for
   `npx hyperframes@latest`; the tracked repo-local CLI is the source of
   truth for the composition contract this skill produces against.
2. `seam-gate.mjs verify` — 0 fail.
3. Restart the preview server (it caches the bundle), spot-check 3-4 beats
   via `__player.seek` on the raw comp page.
4. Do NOT render unless the user asks. After a requested render, verify
   frames from the MP4 (`ffmpeg -ss <t> … -frames:v 1`): captions present,
   background video not black, no tiny/frozen frames.
5. **Caption presence gate — hard fail.** Sample 3-4 frames spread across
   the VO's spoken window (e.g. `t=3`, `t=15`, `t=30`, `t=42` for a 48s VO)
   and confirm the caption rail at `top: 990` renders visible text on each.
   If any frame in a spoken interval is missing captions, the build ships
   uncaptioned — treat it as a red gate and re-check step 5's `LINES`
   population. This is exactly what went wrong on the Jul 13-20 v4 build.

## Project layout

```
projects/active/weekly-changelog-<range>/
├── index.html            # single-doc master (scenes as slides, stamped seams)
├── ledger.json           # vector ledger (seam-stamp input)
├── script-tokens.json    # two-layer script (source of truth for VO + captions)
├── vo-spoken.txt         # generated: spoken layer, one line
├── voiceover.mp3 + vo-words.json + captions.json
├── bgm.mp3               # copy from <SKILL_DIR>/assets/bgm.mp3 (the house track) unless the user supplies one
└── assets/fonts/ + assets/bg-pattern-<dur>s.mp4
```

## Anti-patterns

| Don't                                                 | Instead                                                                                                                                                                                          |
| ----------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| Bullet-point slides for UI changes                    | Mock the surface acting out the change                                                                                                                                                           |
| Fake UI for un-representable items                    | Honest checklist scene                                                                                                                                                                           |
| Plain "JSON"/"CLI" in the TTS text                    | Lexicon spoken forms; display stays standard                                                                                                                                                     |
| Phonetic spellings in captions                        | Captions always render the display layer                                                                                                                                                         |
| Guessing an unknown term's pronunciation              | Ask, then grow the lexicon                                                                                                                                                                       |
| Speaking every changelog item                         | ≤3 per theme; the digest link carries the rest                                                                                                                                                   |
| Green accents everywhere                              | One green moment per scene (#5ef17c)                                                                                                                                                             |
| Starting from a prior video's index.html              | Step 0 — copy `examples/master-skeleton.html` from this skill into `project/index.html`, always                                                                                                  |
| Hand-crafted `@font-face` / WebGL shader / custom BGM | Step 0 — copy this skill's `assets/` verbatim; the skill's assets ARE the brand                                                                                                                  |
| Delivered without CloudFront invalidation             | Run `aws cloudfront create-invalidation` on distribution `E2BSLVSZ7FG3U0` for the exact path after any S3 replace — CDN caches the old file otherwise                                            |
| Shipping with the `LINES` array empty in the scaffold | Step 4 must produce a populated `captions.json`; step 5 must paste it into the IIFE; step 6 gate 5 must confirm captions on rendered frames. An empty `LINES` = uncaptioned ship = re-do the run |
| No `vo-words.json` → skip captions and ship anyway    | Fall back to whisper forced alignment on the produced audio; captions are non-optional                                                                                                           |

Ships with 7 supporting files:

  • examples/master-skeleton.html
  • examples/script-tokens.json
  • references/build-spec.md
  • references/lexicon.json
  • references/script-voice.md
  • references/visualization-registry.md
  • scripts/align-captions.mjs

Mirrored from the author's public source. Install counts from the open skills registry.

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