Cobalt Downloader

Cobalt Downloader

This skill uses Cobalt API to download YouTube videos. Cobalt is an open-source media downloader that handles YouTube's anti-bot measures.

When to Use This Skill

• When yt-dlp fails with bot detection errors
• For business systems that can't manage cookies
• When you need a more reliable download method
• For self-hosted download infrastructure

What This Skill Does

1. Send Request: Submit YouTube URL to Cobalt API
2. Get Download Link: Receive direct download URL
3. Download Content: Fetch video/audio using curl
4. Organize Files: Save with proper naming

Configuration

Option 1: Public Instance (Quick Start)

Use the public Cobalt instance (rate limited):

COBALT_API="https://api.cobalt.tools"

Option 2: Self-Hosted (Recommended for Production)

Deploy your own Cobalt instance:

# Docker deployment
docker run -d -p 9000:9000 ghcr.io/imputnet/cobalt:latest

# Set API endpoint
COBALT_API="http://localhost:9000"

Instructions

Step 1: Check Configuration

# Set Cobalt API endpoint
COBALT_API="${COBALT_API:-https://api.cobalt.tools}"
echo "Using Cobalt API: $COBALT_API"

# Create output directories
mkdir -p ./output/downloads ./temp

Step 2: Download Video

VIDEO_URL="[YOUTUBE_URL]"

# Request download link from Cobalt
RESPONSE=$(curl -s -X POST "$COBALT_API/api/json" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -d "{
    \"url\": \"$VIDEO_URL\",
    \"vCodec\": \"h264\",
    \"vQuality\": \"1080\",
    \"aFormat\": \"mp3\",
    \"filenamePattern\": \"basic\"
  }")

echo "$RESPONSE" | python3 -c "
import sys, json
data = json.load(sys.stdin)
if data.get('status') == 'stream' or data.get('status') == 'redirect':
    print('DOWNLOAD_URL=' + data.get('url', ''))
elif data.get('status') == 'picker':
    # Multiple streams available
    print('DOWNLOAD_URL=' + data['picker'][0]['url'])
else:
    print('ERROR=' + data.get('text', 'Unknown error'))
"

Step 3: Fetch the File

# Extract video ID from URL
VIDEO_ID=$(echo "$VIDEO_URL" | grep -oP 'v=\K[^&]+' || echo "$VIDEO_URL" | grep -oP 'youtu\.be/\K[^?]+')

# Download using the obtained URL
if [ -n "$DOWNLOAD_URL" ]; then
  curl -L -o "./output/downloads/${VIDEO_ID}.mp4" "$DOWNLOAD_URL"
  echo "✅ Downloaded to ./output/downloads/${VIDEO_ID}.mp4"
else
  echo "❌ Failed to get download URL: $ERROR"
fi

Step 4: Audio Only Option

# Request audio only
RESPONSE=$(curl -s -X POST "$COBALT_API/api/json" \
  -H "Content-Type: application/json" \
  -d "{
    \"url\": \"$VIDEO_URL\",
    \"isAudioOnly\": true,
    \"aFormat\": \"mp3\"
  }")

# Download audio
AUDIO_URL=$(echo "$RESPONSE" | python3 -c "import sys,json; print(json.load(sys.stdin).get('url',''))")
curl -L -o "./output/downloads/${VIDEO_ID}.mp3" "$AUDIO_URL"

API Reference

Request Parameters

Response Status

Self-Hosting Cobalt

For production use, self-host Cobalt:

Docker Compose

version: '3.8'
services:
  cobalt-api:
    image: ghcr.io/imputnet/cobalt:latest
    container_name: cobalt
    restart: unless-stopped
    ports:
      - "9000:9000"
    environment:
      - API_URL=http://your-domain:9000
      - API_NAME=cobalt

Benefits of Self-Hosting

• No rate limits
• No dependency on external services
• Better privacy
• Customizable configuration
• Guaranteed availability

Error Handling

Common Errors

Fallback to yt-dlp

If Cobalt fails, fall back to yt-dlp:

if [ -n "$ERROR" ]; then
  echo "Cobalt failed, trying yt-dlp..."
  yt-dlp --cookies ./config/cookies.txt -o "./output/downloads/%(id)s.%(ext)s" "$VIDEO_URL"
fi

Comparison with yt-dlp