This client is no longer supported for Gemini Code Assist for individuals

The error

$ gemini -p "hi"
Error authenticating: IneligibleTierError: This client is no longer supported for Gemini Code Assist for individuals. To continue using Gemini, please migrate to the Antigravity suite of products: https://antigravity.google

Signing in again doesn't help: the browser says the sign-in worked, and the terminal shows the same error.

Why it happens

Google moved Gemini CLI's personal tiers (free, Google AI Pro and Ultra) to its new Antigravity CLI, and since June 18, 2026 Gemini CLI turns them away. Paid Gemini API keys and Gemini Code Assist Standard or Enterprise licenses still work (Google's announcement). Reinstalling, or signing in with another personal account, doesn't change it.

The fix

Keep Gemini CLI, with a paid API key. Setting the key isn't enough on its own if you signed in with Google before: Gemini CLI keeps using the sign-in it saved, and fails the same way. Switch it to the key, with /auth inside Gemini CLI, or in ~/.gemini/settings.json:

{ "security": { "auth": { "selectedType": "gemini-api-key" } } }

and the key in the environment, here in PowerShell:

$env:GEMINI_API_KEY = 'your-key'

With that, Gemini CLI calls the Gemini API instead: on our machine a deliberately wrong key got API key not valid, not this error.

Running it from a script or an agent? Gemini CLI also refuses folders you haven't trusted when it runs headless. Pass --skip-trust, or set GEMINI_CLI_TRUST_WORKSPACE=true.

Or move to Antigravity CLI (agy), which takes personal accounts; Google has a migration guide. DMN doesn't set up Antigravity CLI yet; for Gemini CLI, see DMN for Gemini CLI.