Gemini CLI now warns it isn't optimized for Gemini 4

What changed

Version 0.66.0 adds a banner telling users Gemini CLI isn’t optimized for Gemini 4. The project’s README says Gemini CLI isn’t tuned for the Gemini 4 series and shouldn’t be used to benchmark Gemini models, and recommends Antigravity CLI for Gemini 4 Argon and newer. The same release adds opt-in private network endpoints for MCP OAuth.

Who it affects

Gemini CLI users who want Gemini 4 models, and anyone benchmarking Gemini with Gemini CLI.

What to do

For Gemini 4 work, try Antigravity CLI instead, and don’t treat Gemini CLI results as representative of Gemini 4.

Source: https://github.com/google-gemini/gemini-cli/releases/tag/v0.66.0