YouTube Transcribe
Smart YouTube video transcription with automatic fallback:
- Captions first — extracts existing subtitles (manual or auto-generated) via yt-dlp. Fast, free, no compute.
- Whisper fallback — when no captions exist, downloads audio and transcribes locally with the best available Whisper backend.
When to Use
Use this skill when the user wants to:
- Get a transcript or text version of a YouTube video
- Understand what a YouTube video says without watching it
- Summarize, analyze, or take notes from a YouTube video
- Extract subtitles or captions from a video
Triggers
- "transcribe this YouTube video"
- "what does this video say"
- "get the transcript of [YouTube URL]"
- "summarize this YouTube video" (transcribe first, then process)
- Any YouTube URL shared with a request to understand its content
Requirements
Required:
yt-dlp— for caption extraction and audio downloadpython3
For Whisper fallback (when no captions available):
ffmpeg— for audio processing- One of these Whisper backends (auto-detected in priority order):
mlx-whisper— Apple Silicon native, fastest on Mac (pip install mlx-whisper)faster-whisper— CTranslate2 backend, fast on CUDA/CPU (pip install faster-whisper)openai-whisper— Original Whisper, universal fallback (pip install openai-whisper)
Usage
Basic — transcribe a video
python3 {baseDir}/scripts/transcribe.py "https://www.youtube.com/watch?v=VIDEO_ID"
Specify language for captions
python3 {baseDir}/scripts/transcribe.py "URL" --language zh
Force Whisper (skip caption check)
python3 {baseDir}/scripts/transcribe.py "URL" --force-whisper
JSON output
python3 {baseDir}/scripts/transcribe.py "URL" --format json
Save to file
python3 {baseDir}/scripts/transcribe.py "URL" --output transcript.txt
Options
| Flag | Default | Description |
|---|---|---|
--language |
auto | Preferred subtitle/transcription language (e.g. zh, en, ja) |
--format |
text |
Output format: text, json, srt, vtt |
--output |
stdout | Save transcript to file |
--force-whisper |
false | Skip caption extraction, go straight to Whisper |
--backend |
auto | Whisper backend: auto, mlx, faster-whisper, whisper |
--model |
auto | Whisper model size: auto, large-v3, medium, small, base, tiny |
Environment Variables
| Variable | Description |
|---|---|
YT_WHISPER_BACKEND |
Override Whisper backend selection |
YT_WHISPER_MODEL |
Override Whisper model size |
Auto-Detection
Whisper Backend (priority order)
- MLX Whisper — detected via
import mlx_whisper. Best for Apple Silicon. - faster-whisper — detected via
import faster_whisper. Best for CUDA GPU, good on CPU. - OpenAI Whisper — detected via
import whisper. Universal fallback.
Model Size (based on available RAM)
| RAM | Model | VRAM/RAM Usage |
|---|---|---|
| ≥16GB | large-v3 |
~6-10GB |
| ≥8GB | medium |
~5GB |
| ≥4GB | small |
~2.5GB |
| <4GB | base |
~1.5GB |
Caption Language Priority
When --language is not specified, captions are searched in this order:
- Video's original language
- Chinese variants:
zh-Hant,zh-Hans,zh-TW,zh-CN,zh - English:
en - Any available language
Output Formats
text (default)
Plain text transcript, one continuous block.
json
{
"video_id": "ZSnYlbIYpjs",
"title": "Video Title",
"channel": "Channel Name",
"duration": 708,
"language": "zh",
"method": "captions",
"transcript": [
{"start": 0.0, "end": 5.2, "text": "..."},
...
],
"full_text": "Complete transcript as single string"
}
srt / vtt
Standard subtitle formats with timestamps.