In Discover, tags can be green, red or blue. It first depends on what data you are looking at.
For survey responses, such as CSAT or NPS, tags will either be green or red. This is because an AI tag in survey responses can be mentioned either positively (green) or negatively (red). In the example below, the customer was unable to use their discount but overall happy with the usability of the website.
For support conversations, such as emails and live chats, tags will be blue. This is because an AI tag in conversations is usually describing a problem or a request - no sentiment (positive or negative) is assigned to an AI tag because it is usually implied by the AI tag.