# Music Tracks
## Event Kind
- `36787`: Music Track (addressable)
## Music Track Event
A music track is an addressable event containing metadata about an audio file.
### Format
The `.content` field MAY contain lyrics and production credits in plain text or Markdown.
### Tags
**Required:**
- `d` - Unique identifier for this track
- `title` - Track title
- `artist` - Artist name
- `url` - Direct URL to the audio file
- `t` - At least one tag with value `"music"`
**Optional:**
- `alt` - Human-readable description (NIP-31)
- `image` - URL to album artwork
- `video` - URL to music video file
- `album` - Album name
- `track_number` - Position in album
- `released` - ISO 8601 date (YYYY-MM-DD)
- `t` - Additional genre/category tags
- `language` - ISO 639-1 language code
- `explicit` - Set to `"true"` for explicit content
- `duration` - Track length in seconds
- `format` - Audio format (mp3, flac, m4a, ogg)
- `bitrate` - Audio bitrate (e.g., "320kbps")
- `sample_rate` - Sample rate in Hz
- `zap` - Lightning address for zap splits (multiple allowed, see Zap Splits)
### Example
```json
{
"kind": 36787,
"content": "Lyrics:\n[Verse 1]\n...\n\nCredits:\nProducer: John Doe",
"tags": [
["d", "summer-nights-2024"],
["title", "Summer Nights"],
["url", "https://cdn.blossom.example/audio/abc123.mp3"],
["image", "https://cdn.blossom.example/img/artwork.jpg"],
["video", "https://cdn.blossom.example/video/abc123.mp4"],
["artist", "The Midnight Collective"],
["album", "Endless Summer"],
["track_number", "3"],
["released", "2024-06-15"],
["duration", "245"],
["format", "mp3"],
["t", "music"],
["t", "electronic"],
["alt", "Music track: Summer Nights by The Midnight Collective"]
]
}
```
## Implementation Notes
- Audio files SHOULD be hosted on Blossom servers for permanence
- Video files (music videos) MAY be hosted on Blossom servers or other permanent storage
- Tracks are updatable (addressable events)
- When no `zap` tag is present, use author's profile Lightning address
- Clients MAY auto-detect technical metadata (duration, format, bitrate)
- Clients MAY choose to display video when available, or default to audio-only playback
- Tracks support NIP-25 reactions and NIP-22 comments
- Use `naddr` identifiers to link to tracks
