Gemini CLI Is Dead. Here's the Better Thing That Replaced It According to the article, Google replaced its Gemini CLI with Antigravity CLI at I/O 2026, shifting from a simple prompt-response interface to an agent harness that can spawn sub-tasks, use tools, and run tasks asynchronously in the background. The migration preserves existing features like Skills, Hooks, and Subagents, with Extensions renamed to Antigravity Plugins, and the CLI automatically imports configurations from the old `~/.gemini/` directory. This is a submission for the Google I/O Writing Challenge I opened my terminal on May 20th, ran gemini , and got a deprecation notice. Google shipped Antigravity CLI at I/O 2026 — and killed Gemini CLI the same day. If you use Gemini CLI in your workflow, this already affects you. If you've never touched either, stick around anyway. The mental model shift here is worth understanding before you need it. Why Replace Gemini CLI at All? Gemini CLI was a prompt interface. You send a prompt, you get a response. That's the whole model. Antigravity CLI is an agent harness . The primitive isn't a prompt — it's a running agent that can spawn sub-tasks, use tools, and keep working while you do something else. That's not a rename. That's a different abstraction. The migration is clean though: everything that mattered in Gemini CLI carries over. Skills, Hooks, Subagents — all preserved. Extensions are now called Antigravity Plugins, but the concept is identical. If you had Gemini CLI workflows, the port is mechanical. Install in 30 Seconds curl -fsSL https://antigravity.google/cli/install.sh | bash agy --version No API key prompt during install. Auth happens the first time you invoke an agent. If you have an existing ~/.gemini/ directory, the CLI detects it and imports your Skills automatically. First Command: agy inspect Before you run anything, run this: agy inspect It shows you everything the CLI sees — config files loaded, Skills available global and workspace , Hooks wired up, plugins installed. Think of it as git status for your agent environment. Antigravity CLI v2.0.1 Configuration Global config: ~/.antigravity/config.json Workspace config: .agents/config.json not found Skills global code-review ~/.antigravity/skills/code-review.md commit-message ~/.antigravity/skills/commit-message.md Skills workspace None Hooks None configured Run it first in any new project. It'll save you 20 minutes of debugging why a Skill isn't loading. Skills: Saved Agent Roles A Skill is a markdown file that gives the agent a role, tool access, and task framing. A saved system prompt, with metadata. Create a workspace Skill: mkdir -p .agents/skills php < -- .agents/skills/ux-review.md -- --- name: ux-review description: Reviews a UI screenshot against Nielsen's heuristics tools: read file --- You are a UX analyst. Analyze any UI screenshot against: - Nielsen's 10 Usability Heuristics - WCAG 2.1 accessibility guidelines - Cognitive load principles Return structured findings: what's working, what's broken, and the specific heuristic being violated. Invoke it: agy run --skill ux-review "Review the checkout flow in checkout.png" Skills in .agents/skills/ travel with the project. Skills in ~/.antigravity/skills/ are global. The community Antigravity Awesome Skills https://github.com/sickn33/antigravity-awesome-skills repo has 1,400+ pre-built ones if you'd rather not start from scratch. Bold opinion:The community Skills library is actually the most underrated thing about this ecosystem. You can drop in a production-grade code-review workflow in 90 seconds. Most people skip it and hand-write prompts forever. Hooks: Intercept the Agent Loop Hooks let you fire shell commands at lifecycle moments. Config is JSON: // .agents/config.json { "hooks": { "before tool call": { "command": "echo '$TOOL NAME' .agents/tool-log.txt" } , "on loop stop": { "command": "node scripts/notify.js" } } } Available hook points: before tool call , after model call , on loop stop , on error . The pattern I use on every project: on loop stop writes a summary to a log file, before tool call audits tool use so I can see what the agent actually did. Thirty lines of config, total. Subagents: The Part Gemini CLI Couldn't Do This is the actual upgrade. Gemini CLI was synchronous. You waited. The agent finished. You moved on. Antigravity CLI ships async subagents — dispatch a long-running task to a background agent and keep prompting in the foreground, same session. From inside the TUI: Refactor the auth module to use the new token schema. Dispatching to subagent... While that runs — write a changelog entry for the last 10 commits. Both run in parallel. The subagent reports back when it's done. From the CLI: Dispatch a background agent agy dispatch "Run the full test suite and write a summary to test-report.md" Check active subagents agy agents list Pull output from a specific agent agy agents output