2026-05-20 Google I/O 2026 - Gemini 3.5, Antigravity, and the Agent Bet

Canonical version: 2026-05-20 Google I/O 2026 - Gemini 3.5, Antigravity, and the Agent Bet.

Google I/O 2026 happened yesterday, and Google shipped a lot. New models, a reworked developer platform, agents everywhere. Most of a keynote like this is noise unless you actually build with the stuff. So here's the short version: what changed, what matters for knowledge work, and the one date you shouldn't miss.

The models got faster (and the cheap one isn't cheap anymore)

Gemini 3.5 Flash is the headline model. It's fast — Google claims 4× faster output than other frontier models — and it beats the previous Gemini 3.1 Pro on coding and agentic tasks. Good news. The catch: this is the release where "Flash" stopped meaning "cheap." Pricing jumped to roughly 5× the input cost of Gemini 2.5 Flash. And it isn't just Google. AI API prices are rising across all three big labs. Keep an eye on that one.

Gemini Omni is the other new model: conversational video generation and editing, "like Nano Banana, but for video." Early reactions are mixed. The editing flow impresses; the physics still breaks under pressure. Gemini 3.5 Pro was announced too, with better reasoning, due next month.

The developer story: one platform, and a CLI being retired

This is the part I'd pay attention to. Google folded its developer tooling into a single platform, Google Antigravity, with four surfaces over one shared agent system: Antigravity 2.0 (the desktop app), Antigravity CLI, Antigravity SDK, and Antigravity IDE.

Here's the bit that actually affects people. Gemini CLI is being retired, and Antigravity CLI replaces it. If you use Gemini CLI through a free account or Google AI Pro/Ultra, you have until June 18, 2026 to migrate. Enterprise Gemini Code Assist licences and API-key users keep it. Your Agent Skills, Hooks, Subagents and Extensions all carry over, so the move shouldn't hurt much; just don't get caught by the date.

The scale, for context

A few numbers from the keynote: Google now processes over 3.2 quadrillion tokens a month, up 7× year over year. The Gemini app is at 900 million monthly users, more than double last year. 8.5 million developers build with these models every month. Whatever you think of Google's products, it is not the laggard in this race.

Everything else, briefly

The rest of the firehose: Gemini Spark (a personal 24/7 agent), Daily Brief, Ask YouTube and Ask Maps, voice in Docs and Gmail, Google Pics for image editing, Project Genie and Co-Scientist on the research side, 15 Chrome features for the agentic web, and a new $100/month Google One AI Ultra tier.

References

• Google I/O 2026 collection: https://blog.google/innovation-and-ai/technology/developers-tools/google-io-2026-collection/
• Sundar Pichai on I/O 2026: https://blog.google/innovation-and-ai/sundar-pichai-io-2026/
• Gemini 3.5 Flash announcement: https://blog.google/innovation-and-ai/models-and-research/gemini-models/gemini-3-5/
• Gemini CLI to Antigravity CLI transition: https://developers.googleblog.com/en/an-important-update-transitioning-gemini-cli-to-antigravity-cli/

Related

• Gemini 3.5 Flash
• Gemini 3.5 Pro
• Gemini Omni
• Nano Banana
• Gemini Spark
• Google Antigravity
• Antigravity 2.0
• Antigravity CLI
• Antigravity SDK
• Antigravity IDE
• Gemini CLI
• Gemini Code Assist
• AI API prices are rising
• Gemini 3
• Gemini
• Agentic Era

About Sébastien

I'm Sébastien Dubois, and I'm on a mission to help knowledge workers escape information overload. After 20+ years in IT and seeing too many brilliant minds drowning in digital chaos, I've decided to help people build systems that actually work. Through the Knowii Community, my courses, products & services and my Website/Newsletter, I share practical and battle-tested systems.

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