Token Metadata

Token metadata is the descriptive information attached to a token: its name, symbol and decimal precision for fungible tokens, or for an NFT the title, description, attribute traits and a link to the media file. Contracts usually store only a pointer, such as the URI returned by a tokenURI function, because keeping large files directly on chain would be prohibitively expensive. That pointer may lead to a content-addressed network like IPFS or Arweave, where the hash changes if the file changes, or to an ordinary web server, where the issuer can edit or delete the content at any time. Mutable or centrally hosted metadata is a common weak point, so it is worth checking where a collection actually stores it before buying.