NFT metadata follows the Metaplex standard:
{
"name": "Course Credential",
"symbol": "CRED",
"description": "Completed Introduction to Solana",
"image": "https://arweave.net/...",
"attributes": [
{ "trait_type": "Course", "value": "Intro to Solana" },
{ "trait_type": "Grade", "value": "Gold" }
]
}