Google's Gemini app on macOS now includes Spark, the agentic assistant that acts on your machine rather than just answering questions. It reads and works with local files, connects to Google Tasks and Keep, and can keep a running eye on topics you follow. For now it's a Beta gated to AI Ultra subscribers in the US, 18 and over. The interesting part is where this lands. A general-purpose desktop agent that touches your filesystem, arriving the same week the Mac quietly became the battleground for AI assistants. If you're deciding what an agent gets to do on a work machine, look closely before you hand it your Documents folder.