GitLab team member here.

The training data is documented in https://docs.gitlab.com/ee/user/project/repository/code_sugg...

AI Transparency is important, all available AI features provide documentation for training data, and are built with privacy first.

The GitLab Duo announcement adds more feature details and plans. https://about.gitlab.com/blog/2023/06/22/meet-gitlab-duo-the...

The AI/ML blog series provides insights on experiments, and features being built. https://about.gitlab.com/blog/2023/04/24/ai-ml-in-devsecops-...