Asset Properties Standard

We advice that, when creating/modifying the properties of the assets, Universe owners adhere to the standards that are common to the NFT community. A great reference is provided by OpenSea Standards.

One of the main reasons for adhering to standards is that most marketplaces need to parse the properties in order to display them nicely.

The following are the main things to take into account:

1. mandatory fields: name, description.

2. strongly-suggested extra field: image. For future-proofness, it shall be a pointer to an ipfs route, so that anyone, including the owner of the asset, can upload to ipfs at any point in the future.

3. to associate a video or music file, just place it in the animation_url field; the image field may then be used as a thumbnail for such content.

4. any further properties should go under the attributes field, in the form of an array. Each entry in the array must contain:

   • the name of the property under trait_type

   • the value of the property under value. If the value is a string, place it between ""; if it is numeric, no need.

Here is an example of an asset's typical JSON:

{
  "name": "Supercool Dragon",
  "description": "Legendary creature that loves fire.", 
  "image": "ipfs://QmPCHHeL1i6ZCUnQ1RdvQ5G3qccsjgQF8GkJrWAm54kdtB", 
  "animation_url": "ipfs://QmefzYXCtUXudCy9LYjU4biapHJiP26EGYS8hQjpei472j", 
  "attributes": [ 
    {
      "trait_type": "Rarity", 
      "value": "Scarce"
    }, 
    {
      "trait_type": "Level", 
      "value": 5
    }, 
    {
      "trait_type": "Weight", 
      "value": 123.5
    }  
  ] 
}