source: simon willison: google i/o, gemini spark, antigravity
level: technical
google i/o 2026 brought announcements like gemini spark, a personal ai agent that connects to gmail, calendar, drive, and other google apps. it runs on gemini 3.5 flash and something called antigravity. antigravity includes a desktop app, a go-based cli tool, an sdk, and a vs code fork. the faq mentions antigravity as part of the runtime, but it is unclear why that detail matters.
security for gemini spark is a big question. google says it runs in isolated, ephemeral virtual machines on google cloud, with traffic going through an agent gateway that enforces data loss prevention policies. user credentials are encrypted and not exposed to the agent. however, with many users likely feeding sensitive data into spark, prompt injection risks remain a concern. the author hopes the security is solid to avoid a major agent security failure.
separately, google is replacing the open-source gemini cli with the closed-source antigravity cli. the old tool, written in typescript under apache 2.0 license, will stop working with ai subscriptions on june 18, 2026. this shift to a closed-source go binary wrapped in a python sdk marks a move away from open tools, which may affect developers who relied on the original gemini cli.
why it matters: the move to closed-source tools and the security design of ai agents like gemini spark could impact how developers and enterprises handle sensitive data and build on google's ai platform.
source: simon willison: google i/o, gemini spark, antigravity