Which tool is primarily used for ensuring compliance of the entry summary in customs?

The Automated Trade Environment (ACE) is a critical tool designed to streamline and facilitate trade compliance processes, particularly concerning entry summaries in customs. ACE provides a centralized platform that allows for the electronic submission and processing of import and export data, thereby improving efficiency and compliance with customs regulations.

ACE not only assists in filing entry summaries but also integrates with various systems to ensure that the necessary documentation and compliance checks are completed effectively. This capability is paramount for customs officials and trade operators alike as it helps in monitoring compliance with trade laws and regulations.

The other options, while relevant to various aspects of trade management, do not serve the primary purpose of ensuring compliance specifically for entry summaries in customs. Each of those tools plays its own distinct role in the broader spectrum of trade operations—such as managing trade compliance, dealing with foreign trade zones, or tracking trade agreements—yet they do not focus specifically on the compliance of entry summaries like ACE does.