On January 14, 2015, Buildkite introduced a new feature called API Access Tokens in user settings to enhance security and manage API access. Users can now create tokens with specific permissions and audit their usage. The new tokens are useful for triggering builds from scripts and can be easily rotated by creating new tokens, updating build scripts, and revoking old ones. Existing API tokens have been migrated to the new list and users should update their authentication parameters accordingly.