@@ -41,9 +41,7 @@ stored off-chain in a JSON format. The schema includes the following fields:
4141| \* animation_url | string | URL to a multimedia attachment of the asset. The supported file formats are MP4 and MOV for video, MP3, FLAC and WAV for audio, GLB for AR/3D assets, and HTML for HTML pages. You may use the ?ext={file_extension} query to provide information on the file type. |
4242| \* collection | object | an object with a "name" field specifying the name of the collection, and a “family” field specifying the larger category or group to which the collection belongs. |
4343
44- \* optional
45-
46- ##
44+ \* ` optional `
4745
4846### JSON Schema
4947
@@ -112,6 +110,146 @@ stored off-chain in a JSON format. The schema includes the following fields:
112110}
113111```
114112
113+ ### JSON Basic example
114+
115+ ``` json
116+ {
117+ "name" : " My NFT"
118+ "description" : " This is my awesome NFT"
119+ "image" : " https://example.com/my-nft.jpg"
120+ }
121+ ```
122+
123+ ### JSON Additional fields example
124+
125+ ``` json
126+ {
127+ "name" : " My NFT"
128+ "description" : " This is my non-fungible token."
129+ "image" : " https://example.com/image.png"
130+ "external_url" : " https://example.com"
131+ "animation_url" : " https://example.com/animation.mp4"
132+ "authors" : [
133+ {
134+ "name" : " John Doe"
135+ },
136+ {
137+ "name" : " Jane Smith"
138+ }
139+ ],
140+ "collection" : {
141+ "name" : " My Collection"
142+ "family" : " Art"
143+ }
144+ }
145+ ```
146+
147+ ### JSON Properties example
148+
149+ ``` json
150+ {
151+ "name" : " Sword of the Thunder God"
152+ "description" : " A legendary sword imbued with the power of the thunder god."
153+ "image" : " https://example.com/sword-of-thunder-god.jpg"
154+ "properties" : {
155+ "damage" : 50 ,
156+ "element" : " Thunder"
157+ "rarity" : " Legendary"
158+ },
159+ "external_url" : " https://example.com/sword-of-thunder-god"
160+ "authors" : [
161+ {
162+ "name" : " John Smith"
163+ }
164+ ],
165+ "collection" : {
166+ "name" : " Legendary Weapons"
167+ "family" : " Fantasy"
168+ }
169+ }
170+ ```
171+
172+ ---
173+
174+ ### Pact schema
175+
176+ With marmalade V2, the ** on-chain** metadata schema for non-fungible tokens
177+ (NFTs) has been deprecated. This means that the manifest schema, which was
178+ previously used to store the metadata for NFTs on-chain, is no longer being
179+ used. Instead, a new schema has been introduced, which is off-chain and conforms
180+ to the widely accepted standard for NFT metadata.
181+
182+ ``` pact
183+ (defschema token-schema
184+ manifest:object{manifest}
185+ ...
186+ )
187+ ```
188+
189+ Has been replaced with:
190+
191+ ``` pact
192+ (defschema token-schema
193+ uri:string
194+ ...
195+ )
196+ ```
197+
198+ Token schema now has the following structure:
199+
200+ ``` pact
201+ (defschema token-schema
202+ id:string
203+ uri:string
204+ precision:integer
205+ supply:decimal
206+ policies:[module{kip.token-policy-v2}]
207+ )
208+ ```
209+
210+ - uri: A string representing the URI that points to an external JSON-Schema for
211+ the NFT.
212+
213+ ** Generating t:{hash}**
214+
215+ The previous schema used by Marmalade V1 was called 'manifest', and it consisted
216+ of a URI, a hash value, and an array of data objects. To create a new manifest,
217+ the 'create-manifest' function was used, which took a URI object and an array of
218+ data objects as input. The 'create-datum' function was used to create a data
219+ object, which consisted of a URI object and a datum object. The
220+ 'verify-manifest' function was used to verify that a given manifest was valid,
221+ and the 'enforce-verify-manifest' function was used to enforce the validity of a
222+ manifest.
223+
224+ ``` pact
225+ (defschema token-details
226+ uri:string
227+ precision:integer
228+ policy:module{kip.token-policy-v2}
229+ )
230+ ```
231+
232+ Since ** onchain** manifest is deprecated, token-details schema is hashed.
233+
234+ The reason for hashing the token-details is to capture all the data on the
235+ ledger for cross-chain data. Previously, the manifest was hashed to create a
236+ unique identifier for each NFT, but now the token-details schema is hashed to
237+ create a unique identifier for each NFT.
238+
239+ ## Rationale
240+
241+ ** Why the Manifest was Replaced by URI**
242+
243+ We decided to replace the manifest schema with a URI-based schema. The new
244+ schema for NFT metadata is a simple JSON schema that describes the properties of
245+ the metadata. This schema enables compatibility with various marketplaces and
246+ wallets, making Marmalade tokens more interoperable. By utilising a URI-based
247+ schema, Marmalade tokens can improve scalability, and provide greater
248+ flexibility for developers and most of all simplicity of usage in general.
249+
250+ The decision to move NFT metadata off-chain and use a widely accepted standard
251+ for the metadata schema is a positive step for Marmalade tokens.
252+
115253---
116254
117255The Marmalade v2 metadata standard for Non-Fungible Tokens (NFTs) adheres
@@ -142,9 +280,3 @@ dedication to following established industry norms, ensuring consistency,
142280compatibility, and ease of migration for NFTs. This commitment enables a broader
143281range of users to participate in the vibrant world of digital collectibles while
144282fostering interoperability between different blockchain ecosystems.
145-
146- A more extensive metadata guide with some JSON examples can be found on our
147- github
148- [ here] ( https://github.com/kadena-io/marmalade/blob/v2/README.md#marmalade-v2-metadata-standard )
149-
150- ---
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