The Official Unity Plugin for Codex

Sep 16, 2026

Rachel Zhao - Unity

Director of AI Products

EngineAIEngineAI

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.

Why choose the official Unity plugin for Codex?

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.

Getting started & tooling

Skill/new-unity-projectWhat it doesGuided flow for a brand-new project: gathers the concept, platforms and monetization, installs the Editor while it asks, then creates the project, source control and packages. Does not scaffold gameplay code./unity-cliWhat it doesInstall Editors, create and open projects, manage packages, licenses and modules, build, test and read logs./unity-package-managementWhat it doesAdd, remove, upgrade and discover UPM packages from outside the Editor, including headless and CI installs via the C# PackageManager.Client API, and choosing packages by genre, platform and monetization./generate-editor-search-queryWhat it doesWrites Unity Search queries and opens the Search window for read-only lookups: find materials, prefabs, scenes, shaders, GameObjects, components, labels, paths and references in the current project or scene.SkillWhat it does/new-unity-projectGuided flow for a brand-new project: gathers the concept, platforms and monetization, installs the Editor while it asks, then creates the project, source control and packages. Does not scaffold gameplay code./unity-cliInstall Editors, create and open projects, manage packages, licenses and modules, build, test and read logs./unity-package-managementAdd, remove, upgrade and discover UPM packages from outside the Editor, including headless and CI installs via the C# PackageManager.Client API, and choosing packages by genre, platform and monetization./generate-editor-search-queryWrites Unity Search queries and opens the Search window for read-only lookups: find materials, prefabs, scenes, shaders, GameObjects, components, labels, paths and references in the current project or scene.

UI & text

Skill/uiWhat it doesRouter and UI generalist. Detects which UI system a project uses before any UI code is written, then hands off to UI Toolkit, uGUI or IMGUI. Use for any menu, HUD or screen request where no framework is named./ui-uitkWhat it doesUI Toolkit expert for Unity 6.0+: UXML and USS files, flex layouts, UIDocument, runtime binding, custom elements, manipulators, PanelSettings./ui-uguiWhat it doesuGUI (Canvas-based) expert: Canvas hierarchies, RectTransforms, Layout Groups and prefab UI./ui-imguiWhat it doesIMGUI expert for legacy editor tooling: EditorWindows, custom Inspectors, PropertyDrawers, OnGUI. Maintenance only; new editor UI defaults to UI Toolkit./optimize-text-mesh-proWhat it doesTextMeshPro font stacks, dynamic fallback atlases, padding and sampling ratios, SDF16, AutoSize discipline, CJK fonts, worldspace vs. uGUI, and Memory Profiler font-data capture.SkillWhat it does/uiRouter and UI generalist. Detects which UI system a project uses before any UI code is written, then hands off to UI Toolkit, uGUI or IMGUI. Use for any menu, HUD or screen request where no framework is named./ui-uitkUI Toolkit expert for Unity 6.0+: UXML and USS files, flex layouts, UIDocument, runtime binding, custom elements, manipulators, PanelSettings./ui-uguiuGUI (Canvas-based) expert: Canvas hierarchies, RectTransforms, Layout Groups and prefab UI./ui-imguiIMGUI expert for legacy editor tooling: EditorWindows, custom Inspectors, PropertyDrawers, OnGUI. Maintenance only; new editor UI defaults to UI Toolkit./optimize-text-mesh-proTextMeshPro font stacks, dynamic fallback atlases, padding and sampling ratios, SDF16, AutoSize discipline, CJK fonts, worldspace vs. uGUI, and Memory Profiler font-data capture.

2D & sprites

Skill/2d-pixel-perfectWhat it doesSets up, diagnoses and fixes pixel-perfect 2D rendering for retro and pixel-art games./sprite-editorWhat it doesEdits sprite rectangles, borders, pivots and outlines, and slices sprite sheets automatically, on a grid, or isometrically, via generated ISpriteEditorDataProvider editor scripts./sprite-segment-3x3gridWhat it doesSegments a sprite into a 3×3 grid by color match and outputs a text pattern of which cells match the center — the input format the RuleTile skill consumes./manage-sprite-atlasWhat it doesManages SpriteAtlas through a prebuild pipeline (IPreprocessBuildWithReport): master and variant atlases, texture and packing settings, per-platform configuration, runtime atlas access./tilemap-palette-createWhat it doesCreates a Tile Palette asset for 2D level design, in rectangular, hexagonal or isometric grid layouts./tilemap-ruletile-createemptyWhat it doesCreates a blank RuleTile, HexagonalRuleTile or IsometricRuleTile for custom rule configuration. Only when no sprites are supplied./tilemap-ruletile-createfromsegmentWhat it doesBuilds auto-tiling RuleTiles from existing terrain or edge sprites, converting 3×3 grid patterns into TilingRule neighbor configurations sorted by specificity.SkillWhat it does/2d-pixel-perfectSets up, diagnoses and fixes pixel-perfect 2D rendering for retro and pixel-art games./sprite-editorEdits sprite rectangles, borders, pivots and outlines, and slices sprite sheets automatically, on a grid, or isometrically, via generated ISpriteEditorDataProvider editor scripts./sprite-segment-3x3gridSegments a sprite into a 3×3 grid by color match and outputs a text pattern of which cells match the center — the input format the RuleTile skill consumes./manage-sprite-atlasManages SpriteAtlas through a prebuild pipeline (IPreprocessBuildWithReport): master and variant atlases, texture and packing settings, per-platform configuration, runtime atlas access./tilemap-palette-createCreates a Tile Palette asset for 2D level design, in rectangular, hexagonal or isometric grid layouts./tilemap-ruletile-createemptyCreates a blank RuleTile, HexagonalRuleTile or IsometricRuleTile for custom rule configuration. Only when no sprites are supplied./tilemap-ruletile-createfromsegmentBuilds auto-tiling RuleTiles from existing terrain or edge sprites, converting 3×3 grid patterns into TilingRule neighbor configurations sorted by specificity.

Graphics & rendering

Skill/urp-postprocessingWhat it doesSets up and debugs URP post-processing through the Volume framework: bloom, tonemapping, color adjustments, depth of field, vignette, motion blur./shader-graph-create-custom-nodeWhat it doesGenerates custom Shader Graph nodes from HLSL, including making existing HLSL work as a reflected function node./validate-urp-render-graph-renderer-featureWhat it doesReviews a Unity 6+ URP ScriptableRendererFeature built on the Render Graph API: resource wiring, material binding, execution structure, descriptor usage, global resource exposure./migrate-birp-to-urpWhat it doesPlans, executes and troubleshoots a move from the Built-in Render Pipeline to URP: materials and shaders, pink materials, 2D URP, lighting, baked lightmaps, reflection probes and post-migration visual bugs.SkillWhat it does/urp-postprocessingSets up and debugs URP post-processing through the Volume framework: bloom, tonemapping, color adjustments, depth of field, vignette, motion blur./shader-graph-create-custom-nodeGenerates custom Shader Graph nodes from HLSL, including making existing HLSL work as a reflected function node./validate-urp-render-graph-renderer-featureReviews a Unity 6+ URP ScriptableRendererFeature built on the Render Graph API: resource wiring, material binding, execution structure, descriptor usage, global resource exposure./migrate-birp-to-urpPlans, executes and troubleshoots a move from the Built-in Render Pipeline to URP: materials and shaders, pink materials, 2D URP, lighting, baked lightmaps, reflection probes and post-migration visual bugs.

Audio

Skill/audio-setup-mixersWhat it doesClassifies every Audio Source by what it plays and routes it into the right Audio Mixer Group. Inventories what exists and asks you to add anything missing rather than silently skipping it./optimize-audioWhat it doesCuts audio memory and CPU cost through import settings and mixer configuration. Picks the right Load Type for short clips vs. music vs. ambient beds, and forces 3D audio to mono./setup-vivox-voice-chatWhat it doesIn-game voice and text chat with Unity Vivox: mic permissions on Android and iOS, VAD tuning, push-to-talk, proximity and team channels, mute and volume UI.SkillWhat it does/audio-setup-mixersClassifies every Audio Source by what it plays and routes it into the right Audio Mixer Group. Inventories what exists and asks you to add anything missing rather than silently skipping it./optimize-audioCuts audio memory and CPU cost through import settings and mixer configuration. Picks the right Load Type for short clips vs. music vs. ambient beds, and forces 3D audio to mono./setup-vivox-voice-chatIn-game voice and text chat with Unity Vivox: mic permissions on Android and iOS, VAD tuning, push-to-talk, proximity and team channels, mute and volume UI.

Scene & gameplay

Skill/initialize-ai-navigationWhat it doesSets up AI Navigation — NavMesh surfaces and agents, obstacles, links, modifiers, areas and costs. Walkable meshes, pathfinding, patrol routes, obstacle avoidance./physics-3d-collisionWhat it doesDiagnoses 3D PhysX collision and trigger problems: callbacks not firing, objects passing through each other, raycasts missing, MeshCollider rules, forces that stop working after settling.SkillWhat it does/initialize-ai-navigationSets up AI Navigation — NavMesh surfaces and agents, obstacles, links, modifiers, areas and costs. Walkable meshes, pathfinding, patrol routes, obstacle avoidance./physics-3d-collisionDiagnoses 3D PhysX collision and trigger problems: callbacks not firing, objects passing through each other, raycasts missing, MeshCollider rules, forces that stop working after settling.

Monetization & live ops

Skill/implement-in-app-purchasesWhat it doesImplements, configures and debugs Unity IAP end to end: catalog, the two-step pending-confirm flow, receipt validation, restore, Apple and Google extensions, D2C via Stripe/Coda, and migration off native billing or RevenueCat/Adapty/Essential Kit/UniPay./levelplay-unity-integrationWhat it doesIntegrates the LevelPlay Mediation SDK: rewarded, interstitial and banner ads, network configuration, Android Gradle and iOS CocoaPods dependencies, ATT and privacy, ILRD revenue tracking, migration from Unity Ads or deprecated IronSource APIs./build-live-gameWhat it doesBackend-driven live-service features on Unity Services: battle passes, progression, cloud save, leaderboards, matchmaking, virtual economies, server-authoritative logic, remote config, feature flags, A/B testing, analytics.SkillWhat it does/implement-in-app-purchasesImplements, configures and debugs Unity IAP end to end: catalog, the two-step pending-confirm flow, receipt validation, restore, Apple and Google extensions, D2C via Stripe/Coda, and migration off native billing or RevenueCat/Adapty/Essential Kit/UniPay./levelplay-unity-integrationIntegrates the LevelPlay Mediation SDK: rewarded, interstitial and banner ads, network configuration, Android Gradle and iOS CocoaPods dependencies, ATT and privacy, ILRD revenue tracking, migration from Unity Ads or deprecated IronSource APIs./build-live-gameBackend-driven live-service features on Unity Services: battle passes, progression, cloud save, leaderboards, matchmaking, virtual economies, server-authoritative logic, remote config, feature flags, A/B testing, analytics.

Multiplayer

Skill/setup-multiplayer-servicesWhat it doesReal-time multiplayer with Unity Multiplayer Services: topology choice, hosting, matchmaking, discovery, network setup and session-based play (rooms, parties, lobbies).SkillWhat it does/setup-multiplayer-servicesReal-time multiplayer with Unity Multiplayer Services: topology choice, hosting, matchmaking, discovery, network setup and session-based play (rooms, parties, lobbies).

Platform & localization

Skill/optimize-webWhat it doesSmaller downloads and faster loads for WebGL and WebGPU builds: CDN and server compression, resource stripping, shader variant reduction, KTX textures, quality settings and browser-side profiling./localizationWhat it doesSets up Unity Localization: locales, String and Asset Tables, CJK font support, and Addressables workflows.SkillWhat it does/optimize-webSmaller downloads and faster loads for WebGL and WebGPU builds: CDN and server compression, resource stripping, shader variant reduction, KTX textures, quality settings and browser-side profiling./localizationSets up Unity Localization: locales, String and Asset Tables, CJK font support, and Addressables workflows.

Try the Unity Plugin and send us your feedback

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!