DID spec allows a [DID to publish its OID4VC endpoints](https://w3c.github.io/did-spec-registries/#openid4-verifiable-credential-issuance), so a URL can be fetched from a DIDDocument, e.g. here: https://github.com/digitalbazaar/oid4-client/blob/main/lib/OID4Client.js#L204
DID spec allows a DID to publish its OID4VC endpoints, so a URL can be fetched from a DIDDocument, e.g. here: https://github.com/digitalbazaar/oid4-client/blob/main/lib/OID4Client.js#L204