The Official Unity Plugin for Codex

We're excited to announce that the official Unity plugin for OpenAI’s Codex is available now! The new plugin perfectly coincides with the release of GPT-6 Astra, the newest OpenAI model that makes computer use faster. It turns out that Astra can be a great model to use for building games.

In fact, OpenAI’s own Andrew Walko has shown a great example of how he used Unity and Codex with GPT-6 Astra to create a Unity environment with a few prompts. You’ll note that Andrew created his own Unity plugin as his first step.

The new official Unity Plugin for Codex removes that step, enabling you to build with greater ease and get to your output even faster! Our official plugin gives Codex the skills Unity's own engineers have written for the jobs you do, so it checks your project first, uses the current API, and verifies the result before handing the results to you.

The plugin comes with:

• 31 skills to start with (we’ll continue adding more) written by the Unity teams that own each feature: UI Toolkit and uGUI, 2D and tilemaps, URP and Shader Graph, audio, navigation and physics, IAP and LevelPlay, multiplayer, web and localization.
• Only two commands to set up from terminal or 1-click from the OpenAI plugin directory: add the marketplace, add the plugin. No per-project configuration, and nothing to copy between machines when you move to a new one.
• Unity from your terminal: the unity-cli skill installs Editors, creates and opens projects, manages packages.
• Compatibility with Unity 6+.

The skills in the official Unity Plugin for Codex are developed and maintained by Unity engineers who are experts in the different aspects of the Unity engine so you can expect better output and fewer coding errors.

When you point a general-purpose coding agent at a Unity project today, it answers from the average of everything ever written about Unity. That means a decade of forum threads, tutorials and sample code, much of it written against engine versions that no longer ship. The answer that surfaces is the one that gets repeated most often, rather than the one that is still true today.

The result usually compiles, but you get a sprite atlas hand-authored, asset by asset, instead of packed by a prebuild pipeline. You get a menu whose buttons animate on the way in and snap back on the way out, because the transition was declared on the hover state instead of the base class. You get a URP renderer feature that reads as correct and never runs.

With the official plugin, Codex works from Unity's own guidance for each of those jobs, including deciding more smartly which UI framework your project should use.

It’s this gap between almost right and not quite that is the single most-cited frustration developers have with AI tools. In Stack Overflow's 2025 Developer Survey:

• 66% named "AI solutions that are almost right, but not quite" as their top frustration
• 45% said debugging AI-generated code is more time-consuming
• 46% said they distrust the accuracy of AI output, against 33% who trust it

The official Unity Plugin for Codex closes this gap one job at a time. Each skill teaches the agent how a specific job is actually meant to be done: where a Unity project keeps its assets, how an atlas is supposed to be built, what a URP renderer feature has to satisfy before it will run at all. None of it is new work for you, because every one of those jobs is something you already do in a normal week. What changes is that the agent works from instructions the Unity team wrote, instead of from whatever it picked up about Unity elsewhere.

The community has built plugins with genuinely useful Unity skills, and plenty of them are widely used. What the official one adds is accountability and authenticity, because every skill comes from the Unity engineers who build that system, is tested against how the engine really behaves, goes through our security review, and is updated as the engine ships, so the guidance rarely drifts away from the version you are on. The plugin itself is published by Unity Technologies under the Unity Companion License, and listed in the Codex directory under our own name.

More of you are now starting a game by describing it to a coding agent than by opening a browser, making your way through unity.com, and installing the Hub and an Editor. We want to always give you the flexibility to choose what's best for you. That is why we launched the Unity CLI at Unite Seoul, recently released the official Unity Plugin for Claude Code, and are now introducing the official Unity Plugin for Codex.

Unity's AI tooling has moved quickly this year, from things we were building internally toward things you can pick up and use the day we ship them. The CLI made the engine reachable from any agent you use, and the plugins go further by giving that agent Unity's own answers for the work you need done. Every skill the teams add from here arrives in your tools without any additional work for you.

Install the official Unity Plugin for Codex, open a project, and hand Codex a job you have been putting off — the atlas, the localization pass, in-app purchases.

Read the documentation, tell us what is working and what we need to make better in the Unity Discussions forum, and let us know which skill you want next. We can't wait to see what you create!