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Asset Properties Standard

We strongly advice that, when creating/modifying the properties of the assets in your Universe, you 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 both Freeverse's marketplace and other NFT marketplaces parse the properties in order to nicely display them.

The following are the main things to take into account:

  1. mandatory fields: "name", "description".
  2. suggested extra field: "image". If you want to be future proof, you can set it to point to an ipfs route, so that either you or the owner can upload to ipfs at any point in the future.
  3. 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.
    • So here is an example of an asset's typical JSON:
      {
        "name": "Supercool Dragon",
        "description": "Legendary creature that loves fire.", 
        "image": "ipfs://QmPAg1mjxcEQPPtqsLoEcauVedaeMH81WXDPvPx3VC5zUz", 
        "attributes": [ 
          {
            "trait_type": "Rarity", 
            "value": "Scarce"
          }, 
          {
            "trait_type": "Level", 
            "value": 5
          }, 
          {
            "trait_type": "Weight", 
            "value": 123.5
          }  
        ] 
      }