Code change:
6. <ins> A type is associated with metadata defining, for example, information about the type, a schema defining which claims MAY or MUST appear in the SD-JWT VC, and how they can be displayed. This section defines Type Metadata that can be associated with a type of a SD-JWT VC as well as a method for retrieving the Type Metadata and processing rules.  This Type Metadata is intended to be used, among other things, for the following purposes: Applications using Type Metadata defined in this specification are called "Consumers" in the following.  This typically includes Issuers, Verifiers, and Wallets. 6.1. All examples in this section are non-normative. Type Metadata about the value of a claim value can be retrieved as described in retrieving-type- metadata. Here, the type is . The Type Metadata is retrieved from the URL . The following is an example for a Type Metadata document: 6.2. The Type Metadata document MUST be a JSON object.  The following properties are defined: 6.3. A type can extend another type.  The extended type is identified by the URI in the property.  Consumers MUST retrieve and process Type Metadata for the extended type before processing the Type Metadata for the extending type. The extended type MAY itself extend another type.  This can be used to create a chain or hierarchy of types.  The security considerations described in circular-extends apply in order to avoid problems with circular dependencies. 6.4. 6.4.1. A URI in the claim can be used to express a type.  If the type is a URL using the HTTPS scheme, Type Metadata can be retrieved from the URL , i.e., by inserting after the authority part of the URL. The Type Metadata is retrieved using the HTTP GET method.  The response MUST be a JSON object as defined in type-metadata-format. If the claim is present in the SD-JWT VC, its value MUST be an "integrity metadata" string as defined in Section document-integrity. 6.4.2. A Consumer MAY use a registry to retrieve Type Metadata for a type, e.g., if the type is not a HTTPS URL or if the Consumer does not have access to the URL.  The registry MUST be a trusted registry, i.e., the Consumer MUST trust the registry to provide correct Type Metadata for the type. The registry MUST provide the Type Metadata in the same format as described in type-metadata-format. 6.4.3. Ecosystems MAY define additional methods for retrieving Type Metadata.  For example, a standardization body or a community MAY define a service which has to be used to retrieve Type Metadata based on a URN in the claim. 6.4.4. A Consumer MAY cache Type metadata for a type.  If a hash for integrity protection is present in the Type Metadata as defined in document-integrity, the Consumer MAY assume that the Type Metadata is static and can be cached indefinitely.  Otherwise, the Consumer MUST use the header of the HTTP response to determine how long the metadata can be cached. 6.4.5. Credentials MAY encode Type Metadata directly, providing it as "glue information" to the consumer. For JSON-serialized JWS-based credentials, such Type Metadata documents MAY be included in the unprotected header of the JWS.  In this case, the key MUST be used in the unprotected header and its value MUST be an array of base64url-encoded Type Metadata documents as defined in this specification.  Multiple documents MAY be included for providing a whole chain of types to the Consumer (see extending-type-metadata). A Consumer of a credential MAY use the documents in the array instead of retrieving the respective Type Metadata elsewhere as follows: 7. Both the claim in the SD-JWT VC and various URIs in the metadata document MAY be accompanied by a respective claim suffixed with , in particular: The value MUST be an "integrity metadata" string as defined in Section 3 of W3C.SRI.  A Consumer of the respective documents MUST verify the integrity of the retrieved document as defined in Section 3.3.5 of W3C.SRI. 8. </ins> The Security Considerations in the SD-JWT specification I-D.ietf- oauth-selective-disclosure-jwt apply to this specification. Additionally, the following security considerations need to be taken into account when using SD-JWT VCs: <del> 6.1. </del> <ins> 8.1. </ins> The JWT VC Issuer Metadata configuration is retrieved from the JWT VC Issuer by the Holder or Verifier.  Similar to other metadata

Related discussion:
text: Let's imagine that Giuseppe Marco would be swapped to Marco Giuseppe and pass through a supervised verifier as Marco, while the credential is still valid and verified
I like the idea to define schema and display information in the context of the credential definition (in contrast to issuance protocol) as I believe this information should be consistent across issuers and needs to be available for verifier developers. I also believe some information could be useful at the level of individual credentials for visual customization in the wallet.
we may add: type of binding of the vc ,e.g. key-binding, claim-based-binding, none vct could be either URL linking to the resource directly or an identifier that links to e.g. an (ISO) specification to get the credential metdata IANA registry is probably not a good option versioning of the metadata protection against change e.g. put a hash of metadata in the vc It might be worth to consider reducing the credential format specific Issuer metadata defined in OpenID4VCI and define that in a credential format specific credential metadata resource: However, there will remain issuer-specific things e.g. cryptographic support that should stay in the Issuer Metadata. These would need to be defined in SD-JWT-VC.
Using the VC type metadata, one could also include an ecosystem-specific parameter that contains a that allows you to map to any data model one want. It would also allow automatic fetching and executing the transformation algorithm quite easily.
I prepared a first draft for the SD-JWT VC metadata. I wrote this as a separate draft for working on it, but of course we can consider integrating this into SD-JWT VC — whatever works best. I'm looking forward to your feedback. URL
NAME I like the document and think it's a great start. I think there's a lot more to do around JSON Schema, similar to the work we've put into . I'm happy to help here. Similarly, the display reminds me of , which could be a standalone thing. Perhaps the types document should be transformed to a 'hub' document?
For all these "human readable strings", please make sure to have an i18n story, and ideally reference PRECIS, or DisplayStrings, etc .