---
name: wjs-teaching-english
description: Use when the user wants to teach / learn an English word as a video — turn a single English word into a self-contained HLS "supercut" lesson built from the mira video base. Stitches every season2 clip where the word is spoken (via the search-app API) into one .m3u8, prepended with a Claude-written bilingual word-intro card (word + IPA + 中文 gloss + usage, Volcano TTS) and appended with a 关注王建硕 CTA card. No MP4 burn. Triggers — "teach <word>", "讲讲 <word>", "学英语 <word>", "把 <word> 做成视频", "/wjs-teaching-english <word>".
---
# Teach an English word as a video supercut
Turn one English word into a self-contained HLS lesson:
```
intro.ts (word /IPA/ · 中文 gloss · usage + Volcano TTS)
⋯ EXT-X-DISCONTINUITY
[supercut] every season2 clip where the word is spoken (search-app /api/playlist, COS URLs)
⋯ EXT-X-DISCONTINUITY
cta.ts (关注王建硕 + Volcano TTS)
= search-app/out/<word>.m3u8
```
No MP4 is burned — only the two cards are rendered as tiny `.ts`, re-encoded to
match the supercut's codec so they play in any HLS player.
## Prerequisites (check once)
- `ffmpeg` / `ffprobe` on PATH (Homebrew).
- Python `volcengine` SDK (declared in mira `requirements.txt`, used for TTS):
`python3 -c "import volcengine"`. If missing, ask the user to allow
`pip3 install volcengine==1.0.58` (it's a pinned repo dependency).
- The deployed search-app at `https://search-app-three-kappa.vercel.app`
(default). Override with `SEARCH_APP_BASE=http://localhost:3000` if running
locally (needs Node ≥ 23.6 + `npm start`).
## Steps
1. **Get the word.** A single English word (or short phrase). If the user gave
a sentence, pick the target word.
2. **Write the mini-lesson JSON.** YOU (Claude) author it — no dictionary API.
Keep it accurate and concise. Save to a temp file, e.g. `/tmp/lesson.json`:
```json
{
"word": "love",
"ipa": "/lʌv/",
"pos": "v. / n.",
"gloss": "爱，热爱",
"usage": "下面是它在真实电影里的说法",
"tts_text": "love. 爱。"
}
```
- `tts_text` is read aloud over the intro card — keep it to the word + a
short 中文 gloss (Volcano reads mixed English/中文 fine).
- `usage` is one short line shown on the card (≤ ~20 chars renders best at
low resolutions).
3. **Build it:**
```bash
cd /Users/jianshuo/code/mira/search-app
python3 scripts/build_lesson.py --word love --lesson /tmp/lesson.json
```
Useful flags: `--speaker zh_female_qingxin` (default), `--limit 300` (max
clips), `--no-tts` (silent cards), `--base <url>`, `--out <dir>`.
4. **Report** the printed output path (`search-app/out/<word>.m3u8`) and the
clip count. The `.m3u8` plus its sibling `<word>.intro.ts` / `<word>.cta.ts`
are the deliverable; `out/` is git-ignored.
## Notes
- If the word has no clips, the script exits with "no clips match" and writes
nothing — tell the user and suggest a more common word.
- Intro/CTA are encoded to the FIRST supercut segment's resolution/codec/fps so
the first discontinuity needs no decoder re-init (avoids `bufferAppendError`).
- To play locally: `ffplay search-app/out/<word>.m3u8`, or serve the `out/`
folder over HTTP and open in any HLS player (Safari plays `.m3u8` natively).