TIP-64 - TON Metadata

This standard describes the requirements for metadata. Since in TON both NFTs and the collection are separate contracts, they both have JSON metadata.

Collection metadata

The collection metadata partially resembles ERC-721 standard

{
   "image": "https://link.to.the.collection.image.png",
   "name": "Collection name",
   "description": "Collection description",
   "social_links": [
        "Twitter-link",
        "Telegram-link",
        "etc."
   ],
   "marketplace": "getgems.io"
}

NFT metadata

NFT item metadata is almost identical to the one proposed by the OpenSea except external_url in OpenSea metadata is replaced with content_url in TIP-64. Besides, the present standard is missing such key-value pairs as
background_color:# a-6-character-hex,
animation_url:link-to-a-video,
youtube_url:link-to-youtube.

{
   "name": "NFT name",
   "description": "NFT description",
   "image": "https://link.to.the.item.image.png",
   "content_url": "https://link.to.the.item.image.png",
   "attributes": []
}

There's no particulars given how to form the attributes