Using branch 4.3.1-dev (but I saw that in other branches too) In file src/SOL003/VNFPackageManagement/definitions/SOL003VNFPackageManagement_def.yaml You can see: definitions -> VnfPkgInfo -> properties -> vnfmInfo (at line 136) ```yaml vnfmInfo: description: > Specifies VNFMs compatible with the VNF. This information is copied from the VNFD. See note 3. $ref: "../../General_Definitions/SOL003_def.yaml#/definitions/String" ``` So this is defined as a string in the OpenAPI specs. But SOL003 section 10.5.2.2 defines this as an array of strings (cardinality 1..N) So I think that the file should say ```yaml vnfmInfo: description: > Specifies VNFMs compatible with the VNF. This information is copied from the VNFD. See note 3. type: array items: $ref: "../../General_Definitions/SOL003_def.yaml#/definitions/String" ```