Upskilling Antigravity for the Gemini API
Overcoming Model Knowledge Cutoffs using Agent Skills
Google Antigravity is an agentic IDE that helps you build software. Antigravity offers a variety of models for agentic coding including the latest Gemini and Claude models. If you’re building an app that calls the Gemini API, you may find that the generated code is using old libraries or not calling the latest models - regardless of which models you use. In this post, we'll look at why this happens and how to easily fix it.
In the screenshot below, you can see that we are using “Gemini 3 Pro (High)” (currently Google’s best model) with the following prompt:
create a new python webapp that calls the gemini API using the latest gemini model
Immediately you can see a problem in the code. The app is using the deprecated google-generativeai package and we can see that the code is also calling the outdated gemini-1.5-flash model.
Why does this happen? Shouldn’t Antigravity and Gemini 3 Pro write code that leverages the latest packages and models? Simply put, it has to do with the model’s knowledge cutoff. Even though Gemini 3 Pro was launched in December 2025, the model’s knowledge cutoff is January 2025. Gemini 3 Pro doesn’t know about models and packages that launched afterwards. Therefore, the model is defaulting to older packages and models. This issue is not unique to Gemini and all models face it.
Thankfully there’s a fix for this! Antigravity supports Agent Skills to make this easier. “Agent Skills are a lightweight, open format for extending AI agent capabilities with specialized knowledge and workflows.” We can use Agent Skills to equip Antigravity and Gemini 3 Pro (or whichever model you use) with the latest knowledge.
The Google Gemini team recently launched the Gemini Skills GitHub repository.
This repo contains a skill that Antigravity’s agents can use to guide the model towards using the latest Gemini API packages (across a range of languages) and the latest models.
Once we’ve added this skill to ~/.gemini/antigravity/skills/gemini-api-dev/SKILL.md, we can retry our prompt. We immediately see the desired results.
While AI models are incredibly powerful, their knowledge cutoffs will always be a limiting factor in the fast-paced world of software development. Fortunately, Agent Skills provide a lightweight and effective bridge. By giving Google Antigravity up-to-date context, you can ensure your agentic IDE is always writing modern, relevant code. Head over to the Gemini Skills GitHub repository to grab this skill, or try writing your own custom skills to tailor Antigravity to your specific needs.
