NIP-94 defines a file metadata event (kind 1063) for organizing and classifying shared files on Nostr, enabling relays to filter and organize content effectively.

How It Works

  1. User uploads a file to a hosting service
  2. A kind 1063 event is published with metadata about the file
  3. The event content contains a human-readable description
  4. Structured tags provide machine-readable metadata
  5. Specialized clients can organize and display files systematically

Required and Optional Tags

Core tags:

  • url - Download link for the file
  • m - MIME type (lowercase format required)
  • x - SHA-256 hash of the file

Optional tags:

  • ox - SHA-256 hash of the original file before server transformations
  • size - File size in bytes
  • dim - Dimensions (width x height) for images/video
  • magnet - Magnet URI for torrent distribution
  • i - Torrent infohash
  • blurhash - Placeholder image for previews
  • thumb - Thumbnail URL
  • image - Preview image URL
  • summary - Text excerpt
  • alt - Accessibility description
  • fallback - Alternative download sources

Use Cases

NIP-94 is designed for file-sharing applications rather than social or longform content clients. Suggested applications include:

  • Torrent indexing relays
  • Portfolio-sharing platforms (similar to Pinterest)
  • Software configuration and update distribution
  • Media libraries and archives

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