Buildkite has introduced a new API Access Tokens section in user settings to enhance API access management and security. Users can now create tokens with specific permissions and monitor their usage, facilitating tasks like programmatically triggering builds via scripts. The update simplifies token rotation by allowing users to create new tokens, update scripts, and revoke old ones. Existing API tokens have been migrated to this new system, maintaining their permissions and account access. The previous api_key parameter has been deprecated in favor of the new access_token parameter, as detailed in the updated API Authentication documentation.