To gain access to a project's Head Contracts tool, your Procore user account must be granted 'Read Only' level permissions or higher to the Head Contracts tool. However, users with 'Admin' level permissions to the tool also have an option to mark a head contract as 'Private.' If your user account has not been added to the head contracts 'Private' list, you will see this banner:
In order to view a 'Private' head contract, your user account must be added to the head contract's 'Private' list by a user with 'Admin' permissions on the Head Contracts tool.