Email tags
Overview
Cloud Email Security supports adding markers called tags to emails, to provide a user-defined notation for emails based on different processing properties of a specific email.
Tags can be configured differently for each security rule.
Enable tagging
Tagging can be enabled for several actions or statuses in security rules. For example here the clean tag is added to emails that were allowed:

For further details about enabling and configuring tags see Policy.
Displaying tags
All assigned tags of an email are displayed in Audit > Email History / Email details.

Based on the settings, certain tags may also show up in the front of the delivered email’s subject, in square brackets.

Filtering
Emails can be filtered in Audit > Email History and in Quarantine by the tags applied.
For details see Operating/Email History.