youtube-analysis
DocumentsExtract YouTube transcripts and produce structured concept analysis with multi-level summaries, key concepts, takeaways. Uses youtube-transcript-api with yt-dlp fallback. Triggers on: "analyze youtube video", "youtube transcript", "summarize this video", "extract concepts from video", "video key points", or any youtube.com/youtu.be URL.
How to use this skill
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YouTube Analysis
Extract transcripts from YouTube videos and produce structured concept analysis — key ideas, arguments, technical terms, takeaways, and multi-level summaries — all without API keys or MCP servers.
Reference Files
| File | Purpose |
|---|---|
scripts/fetch_transcript.py | Core transcript + metadata fetcher (CLI + importable) |
scripts/analyze_video.py | Orchestrator: fetch → structure → export scaffold |
scripts/utils.py | URL parsing, timestamp formatting, transcript chunking |
references/analysis-patterns.md | Prompt patterns for each video type |
assets/output-template.md | Markdown template for final output |
Workflow
User provides YouTube URL
│
▼
┌─────────────────────┐
│ Step 0: Deps check │
└────────┬────────────┘
▼
┌─────────────────────┐
│ Step 1: Parse URL │
└────────┬────────────┘
▼
┌─────────────────────┐ ┌──────────────┐
│ Step 2: Transcript │────▶│ yt-dlp │
│ (youtube-t-api) │fail │ (fallback) │
└────────┬────────────┘ └──────┬───────┘
│◀───────────────-────────┘
▼
┌─────────────────────┐
│ Step 3: Metadata │
│ (yt-dlp --dump-json│
└────────┬────────────┘
▼
┌─────────────────────┐
│ Step 4: Claude │
│ analyzes transcript│
└────────┬────────────┘
▼
┌─────────────────────┐
│ Step 5: Export MD │
└─────────────────────┘
Step 0: Ensure Dependencies
Before running any script, verify dependencies are installed:
uv pip install youtube-transcript-api yt-dlp -q
Or run scripts directly with uv run:
uv run --with youtube-transcript-api --no-project python scripts/fetch_transcript.py "URL"
Verify:
python -c "from youtube_transcript_api import YouTubeTranscriptApi; print('OK')"
yt-dlp --version
Step 1: URL Parsing and Validation
Use scripts/utils.py:parse_youtube_url() to extract the video ID. Supported formats:
| Format | Example |
|---|---|
| Standard watch | youtube.com/watch?v=dQw4w9WgXcQ |
| Short URL | youtu.be/dQw4w9WgXcQ |
| Shorts | youtube.com/shorts/dQw4w9WgXcQ |
| Embed | youtube.com/embed/dQw4w9WgXcQ |
| Live | youtube.com/live/dQw4w9WgXcQ |
| With params | youtube.com/watch?v=dQw4w9WgXcQ&t=120&list=PLxxx |
| Bare ID | dQw4w9WgXcQ |
| Mobile | m.youtube.com/watch?v=dQw4w9WgXcQ |
| Music | music.youtube.com/watch?v=dQw4w9WgXcQ |
If parsing fails, ask the user to provide the URL in a standard format.
Step 2: Transcript Extraction
Run fetch_transcript.py to get the transcript:
cd <skill_dir>/scripts
python fetch_transcript.py "YOUTUBE_URL" --lang en
This outputs JSON to stdout. The script:
- Primary path: Uses
youtube-transcript-apito scrape captions directly (no API key) - Fallback path: If primary fails, uses
yt-dlp --write-sub --write-auto-subto extract subtitle files - Language handling: Tries requested language first, falls back to any available transcript
The returned JSON contains both individual timestamped segments and a joined transcript_text field.
Or import as a module (used by analyze_video.py):
from fetch_transcript import fetch_video
data = fetch_video("https://youtube.com/watch?v=VIDEO_ID", lang="en")
Step 3: Metadata Extraction
Metadata is fetched automatically by fetch_transcript.py via yt-dlp --dump-json:
- Title, channel name
- Duration (seconds)
- Upload date (YYYY-MM-DD)
- Description (first 500 chars in scaffold)
- View count
- Tags
No separate step needed — fetch_video() returns everything.
Step 4: Concept Analysis
This is where you (Claude) do the work. The scripts provide raw data; you perform the analysis.
Analysis Depth
Choose based on user request or video duration:
| Depth | When to Use | Sections to Fill |
|---|---|---|
quick | User wants fast overview, or video < 10 min | TL;DR, Key Concepts, Takeaways |
standard | Default for most videos | All template sections |
deep | User wants thorough breakdown, or video > 30 min | All sections + timestamped section-by-section |
Analysis Process
- Read the full transcript from the JSON output
- Identify the video type (or use user-provided hint). See
references/analysis-patterns.mdfor type-specific guidance - Extract key concepts: Main ideas, arguments, claims — each as a bullet with brief explanation
- Identify technical terms: Definitions as presented in the video
- Pull notable statements: Paraphrase key quotes with approximate timestamps
- Synthesize takeaways: Actionable items the viewer should consider
- Write the TL;DR: One to three sentences capturing the core message
- Suggest related topics: Based on concepts mentioned, what should the viewer explore next
For Deep Analysis
Use utils.chunk_transcript() to break the transcript into 5-minute segments, then analyze each chunk with timestamps:
from utils import chunk_transcript
chunks = chunk_transcript(data["transcript"], chunk_minutes=5)
for chunk in chunks:
print(f"[{chunk['start_formatted']} - {chunk['end_formatted']}]")
print(chunk["text"])
Or run the orchestrator with --depth deep:
python analyze_video.py "YOUTUBE_URL" --depth deep
Video Type Patterns
| Type | Key Extraction Focus | See |
|---|---|---|
| Lecture | Thesis, arguments, citations, definitions | references/analysis-patterns.md |
| Tutorial | Steps, tools, prerequisites, gotchas | references/analysis-patterns.md |
| Interview | Perspectives, disagreements, attributed positions | references/analysis-patterns.md |
| Podcast | Topic threads, opinions, recommendations | references/analysis-patterns.md |
| Tech Talk | Architecture, trade-offs, benchmarks, lessons | references/analysis-patterns.md |
| Panel | Consensus vs. disagreement, per-speaker views | references/analysis-patterns.md |
Read references/analysis-patterns.md for detailed extraction guidance per type.
Step 5: Export to Markdown
The orchestrator generates a scaffold:
cd <skill_dir>/scripts
python analyze_video.py "YOUTUBE_URL" --output ./analysis.md --depth standard --type auto
Flags:
--output PATH: Where to write (default:./{sanitized_title}.md)--depth quick|standard|deep: Analysis depth--type auto|lecture|tutorial|interview|podcast|tech-talk|panel: Video type hint--lang CODE: Transcript language (default:en)--json: Output raw JSON instead of Markdown scaffold
The scaffold contains populated metadata and [TO BE ANALYZED] placeholders. Claude replaces these with actual analysis.
Preferred workflow: Run fetch_transcript.py to get JSON, analyze in context, then produce the final Markdown directly using assets/output-template.md as the structure guide. The orchestrator is useful for batch processing or when the user wants a file written.
Error Handling
| Error | Exit Code | Cause | Resolution |
|---|---|---|---|
| URL parse failure | 1 | Invalid or unsupported URL format | Ask user for standard YouTube URL |
| No transcript | 2 | Video has no captions (manual or auto) | Inform user; suggest a different video |
| Video unavailable | 1 | Private, deleted, or geo-blocked | Inform user of the restriction |
| Age-restricted | 1 | Requires authentication | Inform user; yt-dlp may work with cookies |
| Metadata fetch fail | 0 | yt-dlp network issue | Transcript still works; metadata shows "Unknown" |
| Language unavailable | 0 | Requested lang not available | Auto-falls back to available language |
| yt-dlp not installed | 1 | Missing dependency | Run Step 0 dependency installation |
Limitations
- No visual analysis: Transcript-only; slides, diagrams, code on screen, and demos are not captured. Note this in output when relevant.
- Auto-caption quality: Auto-generated captions may contain errors, especially for technical terms, proper nouns, and non-English accents.
- Music videos: Lyrics may not be available as captions. Music-only content produces poor results.
- Live streams: Ongoing live streams may have incomplete or unavailable transcripts.
- Rate limiting: Excessive requests to YouTube may trigger temporary blocks. Space requests if processing multiple videos.
- Language coverage: Best results for English. Other languages depend on caption availability and quality.
- Speaker attribution: Transcripts rarely identify individual speakers. Claude infers from context where possible.