bacchus-labs/youtube-transcript

YouTube Transcript Downloader

This skill helps download transcripts (subtitles/captions) from YouTube videos using yt-dlp.

When to Use This Skill

Activate this skill when the user:

• Provides a YouTube URL and wants the transcript
• Asks to "download transcript from YouTube"
• Wants to "get captions" or "get subtitles" from a video
• Asks to "transcribe a YouTube video"
• Needs text content from a YouTube video

Available Scripts

This skill includes modular scripts in the scripts/ directory:

| Script | Purpose | |--------|---------| | check-ytdlp.sh | Check if yt-dlp is installed, attempt installation if not | | download-transcript.sh | Main workflow: download subtitles with automatic fallback | | whisper-transcribe.sh | Last resort: download audio and transcribe with Whisper | | vtt-to-text.py | Convert VTT subtitle files to plain text with deduplication |

Script Location

# Scripts are located at:
SKILL_DIR="$(dirname "$0")"  # When running from skill directory
# Or use absolute path from wrangler installation

Quick Start

Option 1: Use the Main Download Script

# Download transcript (tries manual subs, then auto-generated)
./scripts/download-transcript.sh "https://www.youtube.com/watch?v=VIDEO_ID"

# Specify output directory
./scripts/download-transcript.sh "https://www.youtube.com/watch?v=VIDEO_ID" ./transcripts

Option 2: Manual Step-by-Step

# 1. Check/install yt-dlp
./scripts/check-ytdlp.sh --install

# 2. Download transcript
./scripts/download-transcript.sh "YOUTUBE_URL"

# 3. If no subtitles available, use Whisper
./scripts/whisper-transcribe.sh "YOUTUBE_URL"

How It Works

Priority Order:

1. Check if yt-dlp is installed - install if needed
2. List available subtitles - see what's actually available
3. Try manual subtitles first (--write-sub) - highest quality
4. Fallback to auto-generated (--write-auto-sub) - usually available
5. Last resort: Whisper transcription - if no subtitles exist (requires user confirmation)
6. Confirm the download and show the user where the file is saved
7. Automatically convert VTT to plain text with deduplication

Script Details

check-ytdlp.sh

Check if yt-dlp is installed and optionally install it.

# Just check
./scripts/check-ytdlp.sh

# Check and install if missing
./scripts/check-ytdlp.sh --install

Exit codes:

• 0 - yt-dlp is available
• 1 - yt-dlp not found and installation not attempted
• 2 - Installation failed

download-transcript.sh

Main workflow script that handles the complete download process.

./scripts/download-transcript.sh <youtube_url> [output_dir]

What it does:

1. Fetches video info (title, ID)
2. Lists available subtitles
3. Tries manual subtitles first
4. Falls back to auto-generated if needed
5. Converts VTT to plain text automatically
6. Cleans up temporary files

Exit codes:

• 0 - Success
• 1 - Invalid arguments
• 2 - yt-dlp not found
• 3 - No subtitles available
• 4 - Download failed

whisper-transcribe.sh

For videos without any subtitles, download audio and transcribe locally.

./scripts/whisper-transcribe.sh <youtube_url> [output_dir] [--auto-confirm]

What it does:

1. Shows file size and duration
2. Asks for confirmation before downloading
3. Checks/installs Whisper if needed
4. Downloads audio as MP3
5. Transcribes with Whisper (base model)
6. Converts to plain text
7. Optionally cleans up audio file

Options:

• --auto-confirm - Skip confirmation prompts (for automation)

Exit codes:

• 0 - Success
• 1 - Invalid arguments
• 2 - yt-dlp not found
• 3 - Whisper not found and user declined installation
• 4 - Download failed
• 5 - Transcription failed
• 6 - User cancelled

vtt-to-text.py

Convert VTT subtitle files to plain text with deduplication.

# Output to file
python3 ./scripts/vtt-to-text.py input.vtt output.txt

# Output to stdout
python3 ./scripts/vtt-to-text.py input.vtt

Features:

• Removes VTT headers and timestamps
• Strips HTML-like tags
• Decodes HTML entities
• Removes duplicate lines (common in auto-generated subs)
• Preserves original speaking order

Manual Commands Reference

If you prefer to run commands manually instead of using the scripts:

Check yt-dlp Installation

which yt-dlp || command -v yt-dlp

Install yt-dlp

# macOS (Homebrew)
brew install yt-dlp

# Linux (apt)
sudo apt update && sudo apt install -y yt-dlp

# Any system (pip)
pip3 install yt-dlp

List Available Subtitles

yt-dlp --list-subs "YOUTUBE_URL"

Download Manual Subtitles

yt-dlp --write-sub --sub-langs "en.*" --skip-download --output "transcript" "YOUTUBE_URL"

Download Auto-Generated Subtitles

yt-dlp --write-auto-sub --sub-langs "en.*" --skip-download --output "transcript" "YOUTUBE_URL"

Get Video Title

yt-dlp --print "%(title)s" "YOUTUBE_URL"

Download Audio Only (for Whisper)

yt-dlp -x --audio-format mp3 --output "audio_%(id)s.%(ext)s" "YOUTUBE_URL"

Transcribe with Whisper

whisper audio.mp3 --model base --output_format vtt

Output Formats

• VTT format (.vtt): Includes timestamps and formatting, good for video players
• Plain text (.txt): Just the text content, good for reading or analysis

The scripts automatically convert VTT to plain text and clean up the VTT file.

Error Handling

Common Issues and Solutions

1. yt-dlp not installed

./scripts/check-ytdlp.sh --install

2. No subtitles available

• Try the Whisper transcription option
• Some videos may be private, age-restricted, or geo-blocked

3. Whisper installation fails

• May require system dependencies (ffmpeg, rust)
• Check available disk space (models require 1-10GB)
• Try: pip3 install openai-whisper

4. Download interrupted

• Check internet connection
• Verify sufficient disk space
• Try again with --no-check-certificate if SSL issues

5. Multiple subtitle languages

• The scripts default to English (en.*)
• Modify the --sub-langs parameter for other languages

Best Practices

• Always check what's available before downloading (--list-subs)
• Verify success at each step before proceeding
• Ask user before large downloads (audio files, Whisper models)
• Clean up temporary files after processing
• Provide clear feedback about what's happening at each stage