The Item Description for the package or service does not have a Summary.
Solution
Click the Item Description tab and provide a Summary before sharing a package or service.
More information
When sharing a package or service, it is important to provide a summary of your package or service so that end users of the package or service will know who created it, where it came from, and when and how it was made. The package or service summary can be added by accessing the Item Description page in the Geoprocessing Package or Service Editor window and editing the appropriate fields.