Minor doc improvement

application/src/main/java/org/thingsboard/server/controller/AssetController.java

@@ -139,7 +139,9 @@ public class AssetController extends BaseController {
             notes = "Creates or Updates the Asset. When creating asset, platform generates Asset Id as " + UUID_WIKI_LINK +
                     "The newly created Asset id will be present in the response. " +
                     "Specify existing Asset id to update the asset. " +
-                    "Referencing non-existing Asset Id will cause 'Not Found' error." + TENANT_OR_CUSTOMER_AUTHORITY_PARAGRAPH, produces = MediaType.APPLICATION_JSON_VALUE)
+                    "Referencing non-existing Asset Id will cause 'Not Found' error. " +
+                    "Remove 'id', 'tenantId' and optionally 'customerId' from the request body example (below) to create new Asset entity. "
+                    + TENANT_OR_CUSTOMER_AUTHORITY_PARAGRAPH, produces = MediaType.APPLICATION_JSON_VALUE)
     @PreAuthorize("hasAnyAuthority('TENANT_ADMIN', 'CUSTOMER_USER')")
     @RequestMapping(value = "/asset", method = RequestMethod.POST)
     @ResponseBody

common/data/src/main/java/org/thingsboard/server/common/data/asset/Asset.java

@@ -52,6 +52,7 @@ public class Asset extends SearchTextBasedWithAdditionalInfo<AssetId> implements
     @Length(fieldName = "label")
     private String label;
 
+    @ApiModelProperty(position = 100, value = "JSON object with External Id from the VCS", accessMode = ApiModelProperty.AccessMode.READ_ONLY, hidden = true)
     @Getter @Setter
     private AssetId externalId;
 
@@ -98,7 +99,7 @@ public class Asset extends SearchTextBasedWithAdditionalInfo<AssetId> implements
         return super.getCreatedTime();
     }
 
-    @ApiModelProperty(position = 3, value = "JSON object with Tenant Id.", readOnly = true)
+    @ApiModelProperty(position = 3, value = "JSON object with Tenant Id.", accessMode = ApiModelProperty.AccessMode.READ_ONLY)
     public TenantId getTenantId() {
         return tenantId;
     }