Google Chat APIs now generally available to all Workspace developers- Google Developers Blog

What this post added

The Google Chat API, previously in Developer Preview for creating spaces and adding members, is now generally available to all Workspace developers. This includes APIs for managing messages, reactions, and attachments. Additionally, a new feature for importing user data into Google Chat is available in Developer Preview, allowing for the migration of existing messages, attachments, reactions, and memberships using "import mode" spaces that preserve historical timestamps and context.