Unity vs Unreal Engine

Agent access

1. ai-native userPoint an agent at llms.txt or agent-oriented docs

   weight 2 · round to Unity
   Unity~partialprobed5/10

   unity.com serves a root llms.txt file (unity-docs-15, unity-docs-16, unity-probe-rt-2) that an agent could be pointed at, but the actual technical documentation site (docs.unity3d.com) returns 404 for llms.txt and has no markdown mirrors of manual pages (unity-probe-1, unity-probe-2, unity-probe-rt-2), so agent-oriented docs coverage is only marketing-site-deep. missing for 10: llms.txt or agent-readable docs covering the actual API/manual reference (docs.unity3d.com), evidence of agents successfully consuming these docs in practice.

   • [claimed-docs] “Unity’s free plan, Unity Personal, is for individuals and small organizations with less than $100K of revenue and funds raised in the last 1…”
   • [claimed-docs] “Create and optimize high-end games and interactive experiences. Bring your team’s vision to life with Unity’s real-time development platform…”
   • [probe] “PROBE runtime (recorded 2026-09-15): unity.com serves a site-root llms.txt ('# Unity — Develop, deploy, and grow with Unity...'), but docs.u…”
   • [probe] “PROBE llms.txt: HTTP 404 at https://docs.unity3d.com/llms.txt”
   • [probe] “PROBE docs-md: HTTP 404 at https://docs.unity3d.com/Manual/index.html.md”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   A direct probe found no llms.txt on Epic's domains, and appending .md to docs URLs returns the HTML SPA shell rather than agent-readable markdown, meaning there is no mechanism to point an agent at machine-readable docs.

   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

2. ai-native userRun the product headlessly / in CI for automation

   weight 2 · round to Unity
   Unity✓fullprobed8/10

   Unity's Editor and Player support extensive command-line arguments (unity-docs-6, unity-docs-7) including an explicit headless mode with no display/input (unity-docs-8), enabling automation and CI pipelines; Unity Hub is also installable headlessly via package managers (unity-probe-rt-3), supporting real-world CI build setups. One community report notes cost barriers to setting up a CI build server (unity-comm-13), but this is a licensing/cost complaint rather than a technical failure of headless capability. Missing for 10: independent hands-on verification of a full CI pipeline example and more detail on batchmode build automation scripts.

   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Run the application in headless mode. In this mode, the application doesn’t display anything or accept user input.”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity Hub installs keylessly from Homebrew (cask unity-hub 3.21.2, 'Management tool for Unity') — the e…”
   • [community] “The extravagant cost of a Unity seat meant we couldn't afford to give anyone except the Unity devs a license... For the same reason, we coul…”

   proof ↗⚑ flag

   Unreal Engine~partialprobed6/10

   Docs show real automation building blocks: command-line launch arguments (unreal-docs-7, unreal-docs-14), UAT commands for cooking/packaging/deploying (unreal-docs-16, unreal-docs-17), and Python editor scripting for automating asset tasks (unreal-docs-4), all of which are commonly used to run Unreal headlessly in CI pipelines. However, there is no explicit first-party 'headless mode' or CI-integration guide, and the probe notes Unreal's docs/repos are largely non-machine-readable (403s, no llms.txt, no official MCP), suggesting automation setup requires manual/expert configuration rather than a turnkey CI story. Missing for 10: dedicated headless-mode documentation, official CI/CD templates (e.g., GitHub Actions), and independent hands-on confirmation of CI pipelines running Unreal successfully.

   • [claimed-docs] “command-line arguments can be an invaluable tool for testing and optimizing your project”
   • [claimed-docs] “Command-line Arguments, also called Additional Launch Parameters, customize how the engine runs on startup.”
   • [claimed-docs] “UnrealEditor.exe <GameName or uproject> -run=cook -targetplatform=<Plat1>+<Plat2>”
   • [claimed-docs] “This command can cook content for a platform, package it up into a platform's native format for distribution, deploys it to the device, and …”
   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

3. ai-native userPlug MCP servers into this product so it can use their tools

   weight 3 · round drawn
   Unity—none0/10

   Evidence shows Unity ships an official MCP *server* (com.unity.ai.assistant) so external AI agents can connect to and control Unity — the opposite direction of this story, which asks whether Unity itself can plug in external MCP servers to use their tools. No evidence indicates Unity's AI Assistant or Editor can act as an MCP client/host consuming third-party MCP servers.

   • [probe] “official MCP server documented at https://docs.unity3d.com/Packages/com.unity.ai.assistant@latest/index.html?subfolder=/manual/integration/u…”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity ships an OFFICIAL MCP server as part of Unity's AI tools (beta) inside the com.unity.ai.assistant…”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   Unreal Engine is a platform/tool (not an agent), so the MCP-server axis fairly applies, but evidence shows no official Epic-maintained MCP server exists (GitHub search for `mcp org:EpicGames` returns 0 results) and the most popular community MCP integration is unmaintained since 2025, meaning there's no first-party way to plug MCP servers into Unreal for tool use.

   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

4. ai-native userConnect an agent via an official MCP server

   weight 3 · round to Unity
   Unity~partialprobed6/10

   Unity ships an official MCP server (unity-mcp-get-started docs, unity.com/features/ai 'View MCP Docs') bundled in the com.unity.ai.assistant package, letting agents connect to the Editor. However it's beta, closed-source with no public repo or standalone package (no keyless handshake), and AI usage is metered via Unity Credits, while the much larger community MCP (CoplayDev/unity-mcp, 14k+ stars) suggests the official one is not the primary integration path. Missing for 10: open-source/self-hostable server, GA (non-beta) status, broader independent adoption evidence of the official server itself.

   • [probe] “official MCP server documented at https://docs.unity3d.com/Packages/com.unity.ai.assistant@latest/index.html?subfolder=/manual/integration/u…”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity ships an OFFICIAL MCP server as part of Unity's AI tools (beta) inside the com.unity.ai.assistant…”
   • [claimed-docs] “Whenever you generate an image, create a 3D model, produce a sound effect, or send a message to the Assistant, you spend Unity Credits from …”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   Unreal Engine is a platform/tool (not itself an agent), so an official MCP server axis applies, but evidence shows no official Epic MCP server exists — a GitHub org search returns 0 results, and the most popular community MCP integration is unmaintained since 2025.

   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

5. ai-native userUse an official CLI

   weight 2 · round drawn
   Unity✓fullprobed7/10

   Unity ships a well-documented official CLI for the Editor and Player, supporting batch/headless mode, custom arguments, and automated build workflows (unity-docs-6/7/8/9, unity-probe-5), which is exactly the kind of scriptable interface an AI agent could drive for CI/automation. Missing for 10: no AI-specific CLI tooling and the docs aren't machine-readable (llms.txt/.md mirrors 404 per unity-probe-rt-2), limiting direct agent ingestion of the CLI reference itself.

   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Run the application in headless mode. In this mode, the application doesn’t display anything or accept user input.”
   • [claimed-docs] “Unity can build your application for different platforms with unique build configurations using build profiles in the Unity Editor.”
   • [probe] “official CLI documented at https://docs.unity3d.com/Manual/EditorCommandLineArguments.html”
   • [probe] “PROBE runtime (recorded 2026-09-15): unity.com serves a site-root llms.txt ('# Unity — Develop, deploy, and grow with Unity...'), but docs.u…”

   proof ↗⚑ flag

   Unreal Engine✓fullprobed7/10

   Unreal ships an official CLI surface: UnrealEditor.exe/UAT commands for cooking, packaging, deploying and running projects, plus documented command-line arguments for automation and testing, and Python editor scripting for scriptable workflows — all first-party and independently confirmed as keylessly fetchable per the probe. missing for 10: explicit AI-native framing or agent-oriented tooling around the CLI, and independent hands-on validation of using it in agentic workflows.

   • [claimed-docs] “command-line arguments can be an invaluable tool for testing and optimizing your project”
   • [claimed-docs] “Command-line Arguments, also called Additional Launch Parameters, customize how the engine runs on startup.”
   • [claimed-docs] “UnrealEditor.exe <GameName or uproject> -run=cook -targetplatform=<Plat1>+<Plat2>”
   • [claimed-docs] “This command can cook content for a platform, package it up into a platform's native format for distribution, deploys it to the device, and …”
   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

6. ai-native userDrive the product through a documented public API

   weight 3 · round to Unity
   Unity✓fullprobed8/10

   Unity ships an extensively documented public Scripting API for editor/runtime automation, plus documented command-line/batchmode interfaces for headless CI-driven builds, and an official MCP server (com.unity.ai.assistant) explicitly for AI-driven control of the editor, corroborated by community MCP adoption. This goes beyond a typical closed product and gives AI-native users multiple documented, programmatic entry points. Missing for 10: a formal OpenAPI/REST spec (docs.unity3d.com openapi probes 404) and independent hands-on validation of the MCP server's completeness.

   • [claimed-docs] “Interacting directly with the public Unity APIs allows for finer control and a greater degree of customization.”
   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Run the application in headless mode. In this mode, the application doesn’t display anything or accept user input.”
   • [claimed-docs] “Unity lets you extend the editor with your own custom inspectors and Editor Windows and you can define how properties are displayed in the i…”
   • [probe] “official MCP server documented at https://docs.unity3d.com/Packages/com.unity.ai.assistant@latest/index.html?subfolder=/manual/integration/u…”
   • [probe] “official CLI documented at https://docs.unity3d.com/Manual/EditorCommandLineArguments.html”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity ships an OFFICIAL MCP server as part of Unity's AI tools (beta) inside the com.unity.ai.assistant…”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity Hub installs keylessly from Homebrew (cask unity-hub 3.21.2, 'Management tool for Unity') — the e…”

   proof ↗⚑ flag

   Unreal Engine~partialprobed6/10

   Unreal ships genuinely documented public APIs — a Python editor-scripting API for automating asset/editor tasks, a C++ gameplay API, and command-line/UAT automation flags — which a user or script can drive programmatically. However, the probe evidence shows these are not AI-native accessible: no official Epic MCP server, no llms.txt, docs served only as an HTML SPA (no .md fetch), and the GitHub source repo is EULA/account-gated returning 404 to unauthenticated API calls, with the leading community MCP abandoned since April 2025. Missing for 10: AI-agent-discoverable/machine-readable API docs, an official MCP or agent-facing interface, and keyless programmatic access to source/API metadata.

   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”
   • [claimed-docs] “there may be cases where you want precise control over when and how Assets are discovered, loaded, and audited. For these cases, the Asset M…”
   • [claimed-docs] “command-line arguments can be an invaluable tool for testing and optimizing your project”
   • [claimed-docs] “Command-line Arguments, also called Additional Launch Parameters, customize how the engine runs on startup.”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

7. ai-native userBuild against official SDKs

   weight 2 · round to Unity
   Unity✓fullprobed7/10

   Unity documents extensive official SDK-style surfaces: the public Scripting API for direct C# integration (unity-docs-11), the Package Manager ecosystem for extending functionality (unity-docs-13), editor extensibility APIs (unity-docs-10), and CLI/automation hooks for headless and CI workflows (unity-docs-6,7,8,9, unity-probe-5). It also ships an official MCP server for AI-assistant integration (unity-probe-4, unity-probe-rt-1), directly relevant to AI-native usage, though distribution is closed (no public repo) and metered via credits rather than a keyless open SDK. Missing for 10: no dedicated multi-language SDK page, no OpenAPI/REST spec (probes show 404s), and no llms.txt/markdown mirror on the actual docs site (only on unity.com marketing pages).

   • [claimed-docs] “Interacting directly with the public Unity APIs allows for finer control and a greater degree of customization.”
   • [claimed-docs] “Packages deliver a wide range of enhancements to Unity through the Package Manager.”
   • [claimed-docs] “Unity lets you extend the editor with your own custom inspectors and Editor Windows and you can define how properties are displayed in the i…”
   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Unity can build your application for different platforms with unique build configurations using build profiles in the Unity Editor.”
   • [probe] “official MCP server documented at https://docs.unity3d.com/Packages/com.unity.ai.assistant@latest/index.html?subfolder=/manual/integration/u…”
   • [probe] “official CLI documented at https://docs.unity3d.com/Manual/EditorCommandLineArguments.html”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity ships an OFFICIAL MCP server as part of Unity's AI tools (beta) inside the com.unity.ai.assistant…”
   • [probe] “PROBE runtime (recorded 2026-09-15): unity.com serves a site-root llms.txt ('# Unity — Develop, deploy, and grow with Unity...'), but docs.u…”

   proof ↗⚑ flag

   Unreal Engine~partialprobed5/10

   Unreal ships extensive official build surfaces — C++ APIs, Python editor-scripting API, Blueprint visual scripting, plugin SDK, and CLI/automation tooling — all documented on dev.epicgames.com, which functions as an official SDK for building games/tools. However, the probe evidence shows these are poorly suited for AI-native/agentic consumption: no official MCP server exists, GitHub source access is gated (404 without auth), main sites 403 non-browser clients, no llms.txt, and docs aren't served as fetchable markdown, undercutting AI-native usability of the SDK. Missing for 10: official MCP server or agent-friendly API, machine-readable/llms.txt documentation, keyless programmatic access to source and APIs.

   • [claimed-docs] “Creating new Gameplay classes in C++, and all changes will be reflected in the Unreal Editor after compiling with either Visual Studio or XC…”
   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”
   • [claimed-docs] “Plugins are collections of code and data that developers can easily enable or disable within the Editor on a per-project basis.”
   • [claimed-docs] “Access to the source code All platforms & features Forums and documentation on the Epic Developer Community”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

Agentic features

1. ai-native userGet AI-generated insights and suggestions from my data inside the product

   weight 2 · round to Unity
   Unity~partialprobed5/10

   Unity ships an in-editor AI Assistant (part of com.unity.ai.assistant, metered via Unity Credits) that can chat, generate images/3D models/sound effects, suggesting some AI-driven help inside the editor, and this is corroborated by a live MCP integration for the Assistant. However, evidence never shows the Assistant producing analytical 'insights' from a user's own project data (e.g., analytics, performance suggestions) — it's framed as generative-content assistance rather than data-driven insight generation. Missing for 10: dedicated documentation of data-analysis/insight features, independent hands-on validation of insight quality, and detail beyond generic 'send a message to the Assistant.'

   • [claimed-docs] “Whenever you generate an image, create a 3D model, produce a sound effect, or send a message to the Assistant, you spend Unity Credits from …”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity ships an OFFICIAL MCP server as part of Unity's AI tools (beta) inside the com.unity.ai.assistant…”
   • [probe] “official MCP server documented at https://docs.unity3d.com/Packages/com.unity.ai.assistant@latest/index.html?subfolder=/manual/integration/u…”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   No evidence in the pack of Unreal Engine surfacing AI-generated insights or suggestions from project data; docs cover Blueprints, C++, Python scripting, plugins, and networking but nothing about analytics/AI-driven suggestions, and the probe notes the engine has no official MCP or AI-native tooling exposure.

   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

2. ai-native userSet up automations that run autonomously in the background

   weight 2 · round drawn
   Unity~partialprobed5/10

   Unity supports background/unattended automation via documented CLI and headless-mode Editor/Player flags for CI-style builds (unity-docs-6/7/8, unity-probe-5, unity-probe-rt-3), and it also ships an official (beta) MCP server for AI-assistant integration (unity-probe-rt-1) that could drive agentic workflows. However, there's no evidence of built-in scheduling, triggers, or a persistent agent-orchestration layer — automation still requires external CI tooling or scripting rather than a native 'set-and-forget' automation feature. Missing for 10: native scheduling/trigger system, documented autonomous agent workflows beyond beta MCP, independent hands-on confirmation of unattended background runs.

   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Run the application in headless mode. In this mode, the application doesn’t display anything or accept user input.”
   • [probe] “official CLI documented at https://docs.unity3d.com/Manual/EditorCommandLineArguments.html”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity ships an OFFICIAL MCP server as part of Unity's AI tools (beta) inside the com.unity.ai.assistant…”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity Hub installs keylessly from Homebrew (cask unity-hub 3.21.2, 'Management tool for Unity') — the e…”

   proof ↗⚑ flag

   Unreal Engine~partialprobed5/10

   Unreal exposes Python editor scripting, commandlets, and UAT/command-line automation that can be scripted to run unattended (e.g., asset processing, cooking, packaging) which supports background automation, but nothing in the evidence describes an AI-native agent framework, scheduler, or official API/MCP for autonomous orchestration — and the probe explicitly notes no official Epic MCP and no machine-readable API, undermining AI-native automation setup. missing for 10: official AI-agent/automation orchestration layer, documented scheduling/trigger system for unattended runs, first-party API or MCP for AI agents to invoke automations.

   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”
   • [claimed-docs] “command-line arguments can be an invaluable tool for testing and optimizing your project”
   • [claimed-docs] “Command-line Arguments, also called Additional Launch Parameters, customize how the engine runs on startup.”
   • [claimed-docs] “UnrealEditor.exe <GameName or uproject> -run=cook -targetplatform=<Plat1>+<Plat2>”
   • [claimed-docs] “This command can cook content for a platform, package it up into a platform's native format for distribution, deploys it to the device, and …”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

3. ai-native userDelegate tasks to a built-in AI assistant inside the product

   weight 3 · round to Unity
   Unity~partialprobed6/10

   Unity docs confirm a built-in AI Assistant (com.unity.ai.assistant) that lets users generate images, 3D models, sound effects, and chat with the Assistant directly inside the Editor, metered via Unity Credits — a genuine in-product AI delegate. However, the feature is explicitly beta, evidence is thin on scope/reliability, and no independent/hands-on corroboration of its usefulness exists. Missing for 10: independent hands-on validation of the Assistant's task quality, detail on task scope/limits beyond asset generation, and confirmation it is GA rather than beta.

   • [claimed-docs] “Whenever you generate an image, create a 3D model, produce a sound effect, or send a message to the Assistant, you spend Unity Credits from …”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity ships an OFFICIAL MCP server as part of Unity's AI tools (beta) inside the com.unity.ai.assistant…”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   No evidence in the pack of any built-in AI assistant inside Unreal Editor that users can delegate tasks to; all documentation covers Blueprints, C++, Python scripting, plugins, and CLI tools, not an AI agent. The probe evidence even notes the lack of any official Epic AI/MCP integration.

   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”
   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”
   • [claimed-docs] “Plugins can add runtime gameplay functionality, modify built-in Engine features (or add new ones), create new file types, and extend the cap…”

   proof ↗⚑ flag

4. ai-native userOperate the product with natural-language commands

   weight 2 · round to Unity
   Unity~partialprobed6/10

   Unity ships an official AI Assistant that accepts natural-language messages (consuming Unity Credits per message) and an official MCP server (beta) integrated into the Editor, per unity-docs-14 and unity-probe-rt-1, showing genuine natural-language operation of the tool. However this is explicitly beta, credit-metered, has no public/open repo (closed distribution), and there's no independent hands-on evidence of its reliability compared to the much larger community MCP project. Missing for 10: independent/hands-on validation of the Assistant's command execution, GA (non-beta) status, and documentation of the scope of natural-language commands it can actually perform.

   • [claimed-docs] “Whenever you generate an image, create a 3D model, produce a sound effect, or send a message to the Assistant, you spend Unity Credits from …”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity ships an OFFICIAL MCP server as part of Unity's AI tools (beta) inside the com.unity.ai.assistant…”
   • [probe] “official MCP server documented at https://docs.unity3d.com/Packages/com.unity.ai.assistant@latest/index.html?subfolder=/manual/integration/u…”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   Evidence shows only traditional scripting/programming interfaces (Blueprints, C++, Python, CLI args) with no natural-language command layer; the probe explicitly notes no official Epic MCP server, no llms.txt, and only an unmaintained community MCP project, meaning there's no documented way to operate Unreal via natural-language commands.

   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”
   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”
   • [claimed-docs] “provides the ability for designers to use virtually the full range of concepts and tools generally only available to programmers”

   proof ↗⚑ flag

Api quality

1. ai-native userExplore an interactive API reference with runnable examples

   weight 2 · round drawn
   Unity—none0/10

   The docs manual and scripting reference exist, but there's no evidence of an interactive API reference with runnable/executable code examples — probes explicitly show no OpenAPI spec, no llms.txt/docs-md mirrors at docs.unity3d.com, and no interactive sandbox is mentioned anywhere in the pack.

   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.unity3d.com/openapi.json, https://docs.unity3d.com/swagger.json, https://docs.unity3d.c…”
   • [probe] “PROBE docs-md: HTTP 404 at https://docs.unity3d.com/Manual/index.html.md”
   • [probe] “PROBE llms.txt: HTTP 404 at https://docs.unity3d.com/llms.txt”
   • [probe] “PROBE runtime (recorded 2026-09-15): unity.com serves a site-root llms.txt ('# Unity — Develop, deploy, and grow with Unity...'), but docs.u…”
   • [claimed-docs] “Interacting directly with the public Unity APIs allows for finer control and a greater degree of customization.”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   The evidence shows only standard static documentation pages (C++, Blueprints, Python scripting, plugins) with no interactive API reference or runnable/executable code examples; the probe evidence explicitly notes Unreal's docs are not even machine-readable (no llms.txt, .md URLs return HTML shell) and there's no official API sandbox or live-code explorer mentioned anywhere.

   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”
   • [claimed-docs] “Creating new Gameplay classes in C++, and all changes will be reflected in the Unreal Editor after compiling with either Visual Studio or XC…”
   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”

   proof ↗⚑ flag

2. ai-native userDownload a machine-readable API spec (OpenAPI or equivalent)

   weight 2 · round drawn
   Unity—none0/10

   Unity is a game engine/editor, not an API-driven service, but the story asks specifically about a machine-readable API spec (OpenAPI or equivalent); probes explicitly confirm none exists — all candidate OpenAPI/Swagger paths return 404 and there is no llms.txt or docs-md mirror on the documentation domain. Since Unity does expose scripting/editor APIs and even MCP tooling, this axis is applicable to its ecosystem but the evidence shows the specific artifact is absent.

   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.unity3d.com/openapi.json, https://docs.unity3d.com/swagger.json, https://docs.unity3d.c…”
   • [probe] “PROBE llms.txt: HTTP 404 at https://docs.unity3d.com/llms.txt”
   • [probe] “PROBE docs-md: HTTP 404 at https://docs.unity3d.com/Manual/index.html.md”
   • [probe] “PROBE runtime (recorded 2026-09-15): unity.com serves a site-root llms.txt ('# Unity — Develop, deploy, and grow with Unity...'), but docs.u…”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   No evidence of an OpenAPI or similar machine-readable API spec; the probe evidence explicitly finds Unreal's docs and APIs are not machine-readable (no llms.txt, .md docs serve HTML shells, no official MCP/API spec), confirming absence rather than just lack of mention.

   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

3. ai-native userTest against a sandbox environment without touching production data

   weight 1 · round drawn
   Unity—none0/10

   No evidence describes a sandbox/test environment for Unity's AI/MCP tooling that isolates test data from production; the pack only covers general Unity engine features, pricing controversy, and MCP server existence with no mention of sandbox vs. production data separation.

   ⚑ flag

   Unreal Engine—none0/10

   The axis applies to this product kind (peer products hold positive or none verdicts on this story), so lack of evidence for an applicable capability is "none", never "na". (na/none harmonized at arena bring-up — see pipeline/scripts/na-harmonize.ts.)

   ⚑ flag

4. ai-native userRely on versioned APIs with a documented deprecation policy

   weight 2 · round drawn
   Unity—none0/10

   Evidence shows Unity exposes scripting/editor APIs and packages (unity-docs-11, unity-docs-13) but nothing documents a versioning scheme or deprecation policy for these APIs, and probes show no OpenAPI spec or machine-readable API docs (unity-probe-3, unity-probe-2). Missing for 10: any documented API versioning scheme, deprecation notices/timelines, or changelog policy for Unity's scripting/runtime APIs.

   • [claimed-docs] “Interacting directly with the public Unity APIs allows for finer control and a greater degree of customization.”
   • [claimed-docs] “Packages deliver a wide range of enhancements to Unity through the Package Manager.”
   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.unity3d.com/openapi.json, https://docs.unity3d.com/swagger.json, https://docs.unity3d.c…”
   • [probe] “PROBE docs-md: HTTP 404 at https://docs.unity3d.com/Manual/index.html.md”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   No evidence pack item documents API versioning conventions or a deprecation policy for Unreal's C++/Blueprint/Python APIs; the docs cover feature usage (Blueprints, C++, plugins, replication) but never mention deprecation macros, version compatibility guarantees, or a documented sunset policy. The probe evidence further shows Unreal's docs/API surface is poorly machine-readable, with no llms.txt or markdown API references that would expose such a policy.

   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

Agent editor

1. ai-native userAn agent can drive the editor and project programmatically — create scenes and nodes, edit properties, trigger builds — through a documented scriptable interface

   weight 3 · round to Unity
   Unity✓fullprobed8/10

   Unity documents a comprehensive scripting/editor extension API (custom inspectors, EditorWindows, AssetDatabase, Package Manager) plus command-line/headless automation for builds (unity-docs-6/7/8/9/10/11/12/13), and ships an official MCP server for AI agents inside the com.unity.ai.assistant package with a dedicated get-started manual page (unity-probe-4, unity-probe-rt-1), reinforced by a large third-party community MCP server (14k+ stars) enabling agent-driven scene/property/build workflows. Missing for 10: no public repo/keyless access to the official MCP server (closed distribution, credit-metered) and no independent hands-on verification of an agent actually creating scenes/nodes end-to-end via the documented interface.

   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Unity can build your application for different platforms with unique build configurations using build profiles in the Unity Editor.”
   • [claimed-docs] “Unity lets you extend the editor with your own custom inspectors and Editor Windows and you can define how properties are displayed in the i…”
   • [claimed-docs] “Interacting directly with the public Unity APIs allows for finer control and a greater degree of customization.”
   • [claimed-docs] “The Asset Database stores information about the original source asset files and their imported counterparts to keep the two sets of data in …”
   • [claimed-docs] “Packages deliver a wide range of enhancements to Unity through the Package Manager.”
   • [probe] “official MCP server documented at https://docs.unity3d.com/Packages/com.unity.ai.assistant@latest/index.html?subfolder=/manual/integration/u…”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity ships an OFFICIAL MCP server as part of Unity's AI tools (beta) inside the com.unity.ai.assistant…”

   proof ↗⚑ flag

   Unreal Engine~partialprobed6/10

   Unreal documents a genuine scriptable interface — the Python Editor Scripting API for asset/property automation (docs-4, docs-12), Blueprints for visual node-based logic (docs-1), and CLI/UAT commands for cooking, packaging and triggering builds (docs-7,14,16,17) — which together let a script or agent create/edit content and trigger builds. However, the probe evidence shows no official Epic MCP server or AI-agent-oriented interface exists (0 results for org:EpicGames MCP repos), the most popular community MCP wrapper is unmaintained since 2025, and the docs themselves are not agent-friendly (SPA HTML, no llms.txt, .md suffix doesn't return markdown), undermining ease of programmatic/agentic access despite the underlying scripting capability being real. Missing for 10: official AI-agent/MCP integration, machine-readable documentation, evidence of an agent actually driving these interfaces end-to-end.

   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”
   • [claimed-docs] “there may be cases where you want precise control over when and how Assets are discovered, loaded, and audited. For these cases, the Asset M…”
   • [claimed-docs] “provides the ability for designers to use virtually the full range of concepts and tools generally only available to programmers”
   • [claimed-docs] “command-line arguments can be an invaluable tool for testing and optimizing your project”
   • [claimed-docs] “UnrealEditor.exe <GameName or uproject> -run=cook -targetplatform=<Plat1>+<Plat2>”
   • [claimed-docs] “This command can cook content for a platform, package it up into a platform's native format for distribution, deploys it to the device, and …”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

Codegen

1. ai-native userLLM-generated code mostly works on the first try — stable, well-documented APIs with abundant public examples the models have seen

   weight 2 · round drawn
   Unity—none0/10

   The evidence pack contains no data on LLM code-generation success rates, model familiarity with Unity's C# API, or first-try correctness of AI-generated scripts — only general docs, pricing drama, and MCP/CLI tooling notes. Without concrete evidence (docs, benchmarks, or community reports) speaking to this axis, it cannot be credited.

   ⚑ flag

   Unreal Engine—none0/10

   No evidence directly addresses whether LLM-generated Unreal C++/Blueprint code works reliably on first try; the pack only shows general API docs exist and community comments about C++ complexity and blueprint limitations. The probe evidence even indicates docs are poorly machine-readable (403s, no llms.txt, gated source) which undercuts the 'abundant examples models have seen' premise but isn't a direct test of code-gen success either.

   • [claimed-docs] “Creating new Gameplay classes in C++, and all changes will be reflected in the Unreal Editor after compiling with either Visual Studio or XC…”
   • [community] “My main problem with UE is C++, I don't want to even try to download files or read json in a blueprint.”
   • [community] “blueprints are great for prototyping, but once you have too much complexity in a BP it can easily cascade inefficiencies to the point it bec…”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

Copilot

1. ai-native userAn official AI assistant inside the engine helps with engine tasks — generating scripts, answering API questions, scaffolding scenes or assets

   weight 2 · round to Unity
   Unity~partialprobed6/10

   Unity has an official in-editor "Assistant" — docs confirm it exists and consumes Unity Credits for actions like generating images/models/messages (unity-docs-14), and runtime probes confirm Unity's AI tools (beta) including an MCP integration bundled in the com.unity.ai.assistant package (unity-probe-rt-1, unity-probe-4). However, the evidence pack lacks first-party documentation specifically describing script generation, API Q&A, or scene/asset scaffolding workflows for the assistant, and confirms it's still beta with closed distribution. Missing for 10: dedicated docs/examples showing the Assistant generating scripts or scaffolding scenes, independent hands-on reviews of assistant output quality.

   • [claimed-docs] “Whenever you generate an image, create a 3D model, produce a sound effect, or send a message to the Assistant, you spend Unity Credits from …”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity ships an OFFICIAL MCP server as part of Unity's AI tools (beta) inside the com.unity.ai.assistant…”
   • [probe] “official MCP server documented at https://docs.unity3d.com/Packages/com.unity.ai.assistant@latest/index.html?subfolder=/manual/integration/u…”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   No evidence of an official in-engine AI assistant for generating scripts, answering API questions, or scaffolding scenes; the pack only covers Blueprints, C++, Python editor scripting, and plugins as manual tooling. The probe evidence explicitly notes no official Epic MCP/AI integration and that the most popular community MCP project is unmaintained.

   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”
   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”

   proof ↗⚑ flag

Inference

1. game developerRun ML models inside the game — an official inference runtime for on-device model execution

   weight 1 · round drawn
   Unity—none0/10

   The evidence pack covers Unity's editor AI Assistant, MCP integration, and general engine features, but contains no mention of an on-device ML inference runtime (e.g., Unity Sentis/Barracuda) for running models inside a shipped game. Absence of evidence for this applicable capability means it cannot be credited.

   ⚑ flag

   Unreal Engine—none0/10

   The evidence pack contains no mention of an on-device ML inference runtime (e.g., NNE, ONNX Runtime integration) for Unreal Engine; documentation citations cover Blueprints, C++, Python scripting, plugins, networking, and packaging, but nothing about running ML models in-game. Since game engines can plausibly ship such runtimes, this axis applies, but no supporting evidence exists.

   ⚑ flag

Formats

1. technical artistStandard interchange formats — glTF, FBX, USD — import cleanly

   weight 2 · round drawn
   Unity—none0/10

   The evidence pack never mentions glTF, FBX, or USD import specifically — only generic Asset Database and packaging docs are cited, with no documentation or community proof of clean interchange-format import. Since format import is a fair and expected axis for a game engine's asset pipeline, absence of evidence means 'none' rather than 'na'.

   ⚑ flag

   Unreal Engine—none0/10

   The evidence pack contains no documentation, community, or probe citations addressing glTF, FBX, or USD import functionality in Unreal Engine; all provided docs cover Blueprints, C++, plugins, networking, and licensing instead. Since asset-pipeline import is a fair and applicable axis for a game engine, but no supporting evidence exists in this pack, the verdict is none.

   ⚑ flag

Import

1. technical artistAsset import is automatable — import hooks, presets, and pipeline scripts process incoming assets without hand-clicking each one

   weight 2 · round to Unreal Engine
   Unity~partialclaimed5/10

   Unity's docs confirm scripting APIs, editor extensibility, and an Asset Database that syncs source and imported assets, plus command-line automation for headless/batch operations—together implying pipeline scripting is possible, but no evidence specifically documents AssetPostprocessor import hooks or importer presets, the actual mechanism artists would use to automate imports. missing for 10: explicit documentation of AssetPostprocessor/import-hook API, importer preset system, and a hands-on example of a pipeline script processing incoming assets without manual clicks.

   • [claimed-docs] “Unity lets you extend the editor with your own custom inspectors and Editor Windows and you can define how properties are displayed in the i…”
   • [claimed-docs] “Interacting directly with the public Unity APIs allows for finer control and a greater degree of customization.”
   • [claimed-docs] “The Asset Database stores information about the original source asset files and their imported counterparts to keep the two sets of data in …”
   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Run the application in headless mode. In this mode, the application doesn’t display anything or accept user input.”
   • [claimed-docs] “Packages deliver a wide range of enhancements to Unity through the Package Manager.”

   proof ↗⚑ flag

   Unreal Engine~partialclaimed6/10

   Docs confirm Python scripting can automate asset-management tasks like LOD generation, and the Asset Manager gives programmatic control over asset discovery/loading, while Plugins can add new file-type handling — together these support scripted, non-interactive asset pipelines. However, there's no explicit documentation of dedicated 'import hooks' (e.g. post-import delegates/factories) or preset-based automated import workflows, and no independent/community confirmation that artists actually use this for hands-off batch import. missing for 10: explicit import-hook/factory API docs, named import-preset tooling, and third-party/community validation of automated import pipelines.

   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”
   • [claimed-docs] “provides a framework for managing Assets that can divide content into chunks that make sense in the context of your project”
   • [claimed-docs] “there may be cases where you want precise control over when and how Assets are discovered, loaded, and audited. For these cases, the Asset M…”
   • [claimed-docs] “Plugins can add runtime gameplay functionality, modify built-in Engine features (or add new ones), create new file types, and extend the cap…”
   • [claimed-docs] “Plugins are collections of code and data that developers can easily enable or disable within the Editor on a per-project basis.”

   proof ↗⚑ flag

Marketplace

1. game developerA large asset store or package ecosystem gives me ready-made models, tools, and plugins

   weight 2 · round to Unity
   Unity✓fullprobed9/10

   Unity's Package Manager and Asset Database provide a structured pipeline for packages/assets (unity-docs-12, unity-docs-13), and Unity operates a large public Asset Store ecosystem for third-party models, tools, and plugins, corroborated by community references to a massive Store with hundreds of assets (unity-comm-6) and thriving community add-ons like the 14k-star community MCP server (unity-probe-rt-1) showing ecosystem breadth. Missing for 10: no first-party evidence pack citation of Asset Store size/catalog numbers or independent reviews specifically praising asset variety.

   • [claimed-docs] “The Asset Database stores information about the original source asset files and their imported counterparts to keep the two sets of data in …”
   • [claimed-docs] “Packages deliver a wide range of enhancements to Unity through the Package Manager.”
   • [community] “Unity basically told us we were not welcome back to their Store, ever, even if we removed all LGPL code. Yet there are currently hundreds of…”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity ships an OFFICIAL MCP server as part of Unity's AI tools (beta) inside the com.unity.ai.assistant…”

   proof ↗⚑ flag

   Unreal Engine~partialprobed5/10

   Docs show a genuine plugin and asset-management ecosystem (plugins can add gameplay features, new file types, editor extensions; Asset Manager for content organization) and community comment notes strong third-party program/community support, but there is no direct evidence in the pack describing the actual Marketplace/Fab asset store, its catalog size, or the quality of ready-made models — the probe entry only notes fab.com exists but is API-gated, not its content richness. Missing for 10: concrete marketplace/store catalog evidence, examples of ready-made models/tools available, and independent user reviews of the store experience.

   • [claimed-docs] “Plugins can add runtime gameplay functionality, modify built-in Engine features (or add new ones), create new file types, and extend the cap…”
   • [claimed-docs] “Plugins are collections of code and data that developers can easily enable or disable within the Editor on a per-project basis.”
   • [claimed-docs] “provides a framework for managing Assets that can divide content into chunks that make sense in the context of your project”
   • [claimed-docs] “there may be cases where you want precise control over when and how Assets are discovered, loaded, and audited. For these cases, the Asset M…”
   • [community] “Unreal was already the best engine purely on being easy to work with, support from third party programs and community, none of those things …”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

1. ai-native userPerform bulk operations across many items at once

   weight 2 · round to Unreal Engine
   Unity~partialclaimed4/10

   Unity's scripting API, AssetDatabase, and command-line/batch-mode automation (unity-docs-6/7/8/11/12) allow developers to write editor scripts that iterate over many assets or objects programmatically, which supports bulk operations, but there is no dedicated 'bulk operations' feature or AI-native tooling for it documented. Missing for 10: explicit bulk-edit/batch-apply feature, AI-agent-driven bulk workflows, and independent hands-on evidence of performing bulk operations at scale.

   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Run the application in headless mode. In this mode, the application doesn’t display anything or accept user input.”
   • [claimed-docs] “Interacting directly with the public Unity APIs allows for finer control and a greater degree of customization.”
   • [claimed-docs] “The Asset Database stores information about the original source asset files and their imported counterparts to keep the two sets of data in …”

   proof ↗⚑ flag

   Unreal Engine~partialprobed5/10

   Unreal's Python editor-scripting API and Asset Manager are documented to automate time-consuming asset tasks (e.g., batch-generating LODs for Static Meshes) and manage large sets of Assets in chunks, which supports bulk operations across many items, and UAT/command-line tooling and cooking commands support batch build/deploy across multiple platforms/targets. However there is no concrete first-party example of an AI-native agent performing bulk edits, no official MCP server, and the probe evidence flags Unreal as the least machine-readable/agent-accessible of comparable products (gated APIs, 403s, no llms.txt), undercutting AI-native automation-depth claims. Missing for 10: worked examples of bulk operations orchestrated end-to-end, official AI/agent tooling or MCP integration, independent hands-on confirmation of scripted bulk workflows.

   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”
   • [claimed-docs] “provides a framework for managing Assets that can divide content into chunks that make sense in the context of your project”
   • [claimed-docs] “there may be cases where you want precise control over when and how Assets are discovered, loaded, and audited. For these cases, the Asset M…”
   • [claimed-docs] “UnrealEditor.exe <GameName or uproject> -run=cook -targetplatform=<Plat1>+<Plat2>”
   • [claimed-docs] “This command can cook content for a platform, package it up into a platform's native format for distribution, deploys it to the device, and …”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

2. ai-native userDefine rules that trigger actions automatically on events

   weight 3 · round to Unreal Engine
   Unity~partialclaimed4/10

   Unity's scripting API and editor extensibility let developers write custom event-driven code (e.g. callbacks, custom inspectors, command-line automation of build/launch workflows), which can be used to trigger actions on events, but the evidence never documents an actual declarative 'rules that trigger actions on events' system or AI-native automation trigger framework. Missing for 10: a documented rules/trigger engine (e.g. webhook-style or event-condition-action config), AI-specific automation hooks, and independent confirmation that non-scripted users can define such rules.

   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Unity lets you extend the editor with your own custom inspectors and Editor Windows and you can define how properties are displayed in the i…”
   • [claimed-docs] “Interacting directly with the public Unity APIs allows for finer control and a greater degree of customization.”

   proof ↗⚑ flag

   Unreal Engine✓fullcommunity6/10

   Unreal's Blueprint visual scripting and C++ delegate system explicitly support binding functions to be invoked automatically at a future time/event (dynamic delegates), and Blueprints expose event graphs for designers to wire up event-triggered logic without code. Community commentary confirms Blueprints are used for prototyping event-driven logic though complexity pushes users to C++. Missing for 10: explicit documentation of Event Dispatchers/Event Graph event-binding UI, and independent hands-on validation of rule-trigger reliability at scale.

   • [claimed-docs] “provides the ability for designers to use virtually the full range of concepts and tools generally only available to programmers”
   • [claimed-docs] “You can dynamically bind a delegate to a member function of an arbitrary object, calling the function on the object at a future time”
   • [community] “blueprints are great for prototyping, but once you have too much complexity in a BP it can easily cascade inefficiencies to the point it bec…”

   proof ↗⚑ flag

3. ai-native userSchedule recurring jobs or workflows

   weight 2 · round drawn
   Unity—none0/10

   Unity's evidence shows command-line/headless automation for builds (unity-docs-6/7/8, unity-probe-rt-3) which could be wired into external schedulers, but there is no evidence of any native recurring-job or workflow-scheduling feature inside Unity or its AI tooling. missing for 10: any built-in scheduler/cron equivalent, workflow orchestration UI, or documented recurring automation trigger.

   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Run the application in headless mode. In this mode, the application doesn’t display anything or accept user input.”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity Hub installs keylessly from Homebrew (cask unity-hub 3.21.2, 'Management tool for Unity') — the e…”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   Evidence shows Unreal has CLI automation, Python editor scripting, and UAT commands for one-off automation tasks (e.g. asset processing, cooking/packaging), but nothing about built-in scheduling of recurring jobs or workflows — that would require external tooling like Jenkins/cron, which isn't documented here.

   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”
   • [claimed-docs] “command-line arguments can be an invaluable tool for testing and optimizing your project”
   • [claimed-docs] “Command-line Arguments, also called Additional Launch Parameters, customize how the engine runs on startup.”
   • [claimed-docs] “UnrealEditor.exe <GameName or uproject> -run=cook -targetplatform=<Plat1>+<Plat2>”
   • [claimed-docs] “This command can cook content for a platform, package it up into a platform's native format for distribution, deploys it to the device, and …”

   proof ↗⚑ flag

4. ai-native userVersion, review, and roll back my automations

   weight 1 · round drawn
   Unity—none0/10

   The axis applies to this product kind (peer products hold positive or none verdicts on this story), so lack of evidence for an applicable capability is "none", never "na". (na/none harmonized at arena bring-up — see pipeline/scripts/na-harmonize.ts.)

   ⚑ flag

   Unreal Engine—none0/10

   The evidence pack covers Blueprints, C++, Python scripting, plugins, asset management, and cooking, but contains no mention of version control integration, change review/diffing, or rollback mechanisms for Blueprints, Python scripts, or other automations. This is a plausible axis for a dev engine (e.g., source control on Blueprints), but no supporting evidence exists.

   ⚑ flag

2d

1. game developer2D is a first-class workflow — sprites, tilemaps, 2D physics — not a 3D afterthought

   weight 2 · round to Unity
   Unity~partialclaimed3/10

   Only unity-docs-1's tagline ('Build 2D and 3D games for any platform') references 2D at all; the rest of the evidence pack is dominated by 3D rendering, multiplayer, and platform-build docs with no mention of sprites, Tilemap, 2D physics, or 2D-specific tooling. Missing for 10: dedicated 2D sprite/animation docs, Tilemap system evidence, 2D physics engine documentation, and any community corroboration that 2D is treated as first-class rather than a side feature.

   • [claimed-docs] “Build 2D and 3D games for any platform”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   The evidence pack contains no mention of sprites, tilemaps, Paper2D, or 2D physics support in Unreal Engine—only C++, Blueprints, plugins, networking, and licensing topics. Since a 3D-first engine could plausibly ship a first-class 2D workflow, this axis applies, but no evidence documents it, so the story is unsupported.

   ⚑ flag

Performance

1. game developerProfile and scale — a real profiler, plus data-oriented paths (ECS, jobs, instancing) when scenes get heavy

   weight 2 · round drawn
   Unity—none0/10

   The evidence pack contains no mention of Unity's Profiler, ECS/DOTS, Job System, or GPU instancing — only generic claims about rendering/visuals, scripting APIs, and CLI/build tooling. Since this axis clearly applies to a game engine but no evidence in the pack substantiates the specific profiling or data-oriented tech stack, it must be scored as none. missing for 10: any mention of the Unity Profiler, ECS/DOTS, Job System, Burst compiler, or GPU instancing documentation/evidence.

   ⚑ flag

   Unreal Engine—none0/10

   The evidence pack contains no documentation or community evidence about Unreal Insights, stat/profiling commands, GPU profiling, or data-oriented paths like Mass Entity/ECS, job systems, or GPU instancing — only generic command-line-argument docs mentioning 'testing and optimizing' in passing. Profiling and data-oriented scaling are core, expected capabilities for a AAA game engine, so the axis applies, but nothing in the pack demonstrates a real profiler or ECS/jobs/instancing systems.

   • [claimed-docs] “command-line arguments can be an invaluable tool for testing and optimizing your project”
   • [claimed-docs] “Command-line Arguments, also called Additional Launch Parameters, customize how the engine runs on startup.”

   proof ↗⚑ flag

Physics

1. game developerBuilt-in physics — rigid bodies, collisions, raycasts — works out of the box

   weight 2 · round drawn
   Unity—none0/10

   The evidence pack contains no documentation, community discussion, or probe results that specifically mention Unity's physics engine, rigid bodies, colliders, or raycasting — only generic references to building 2D/3D games, scripting APIs, and editor extensibility. Absence of evidence for this well-known capability must be scored as 'none' rather than inferred from outside knowledge.

   ⚑ flag

   Unreal Engine—none0/10

   The evidence pack contains no documentation, community reports, or probes specifically addressing Unreal's physics system (rigid bodies, collision detection, raycasting, Chaos/PhysX). Coverage is entirely about Blueprints, C++, plugins, asset management, networking, licensing, and community sentiment on cost/usability — none of which substantiates the built-in physics story.

   ⚑ flag

Rendering

1. game developerThe engine ships a modern production 3D renderer — PBR materials, global illumination or baked lighting, shadows, post-processing

   weight 3 · round to Unity
   Unity~partialclaimed7/10

   Unity's docs confirm a modern rendering pipeline is offered ('scalable, captivating visuals using the latest advances in rendering, lighting, and visual effects') and marketing pages reference real-time 3D rendering/visual fidelity, consistent with Unity's known HDRP/URP pipelines supporting PBR, GI, shadows, and post-processing. However, the evidence pack is thin on specifics — no direct mention of PBR materials, baked/real-time GI systems, shadow techniques, or the post-processing stack by name. missing for 10: explicit documentation of PBR material workflow, GI/lightmapping details, shadow cascade features, post-processing stack/volume framework, and independent hands-on corroboration of rendering quality.

   • [claimed-docs] “Elevate your scenes with scalable, captivating visuals using the latest advances in rendering, lighting, and visual effects.”
   • [claimed-docs] “Build and review 3D projects in real time”
   • [claimed-docs] “Create and optimize high-end games and interactive experiences. Bring your team’s vision to life with Unity’s real-time development platform…”

   proof ↗⚑ flag

   Unreal Engine~partialcommunity5/10

   Community evidence confirms Unreal's renderer includes Lumen for real-time global illumination/reflections and general praise for lighting quality, supporting the GI/rendering claim, but the evidence pack lacks first-party documentation or hands-on confirmation of PBR material workflows, shadow systems, or the post-processing pipeline explicitly. missing for 10: explicit docs/evidence on PBR material editor, shadow mapping/ray-traced shadows, and post-process volume/effects stack.

   • [community] “Lumen implements efficient Software Ray Tracing, allowing for global illumination and reflections to run on a wide range of video cards, whi…”
   • [community] “For someone who's actually using UE4 as an artistic break for web dev, I thoroughly recommend it. It allows you to create great environments…”

   proof ↗⚑ flag

Collaboration

1. studio leadThe project format and tooling play well with version control and multi-person teams — mergeable scenes, diffable text formats, or built-in collaboration

   weight 2 · round to Unity
   Unity~partialclaimed2/10

   Evidence only offers a vague marketing tagline ('Collaborate and iterate quickly with your team') with no detail on scene serialization format, diffability, merge tooling, or a named collaboration/VCS product; nothing describes mergeable scenes or text-based diff-friendly formats. Missing for 10: documentation of YAML/text scene serialization mode, a smart-merge tool for scenes/prefabs, and details of a built-in version-control/collaboration product (e.g. Unity VCS/Plastic) with independent corroboration.

   • [claimed-docs] “Collaborate and iterate quickly with your team”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   The evidence pack contains no mention of Unreal's scene/level file formats, diffability, source-control integration (e.g., Perforce/Git-LFS workflows), or any built-in multi-user collaboration tooling; it only covers Blueprints, C++, plugins, networking replication, and licensing. Missing for 10: any documentation or community evidence on .uasset/.umap format mergeability, text-based diffable formats, or built-in collaboration features like Multi-User Editing.

   ⚑ flag

Editor

1. technical artistA full visual editor — viewport, inspector, prefabs/scene composition — is the primary way to build levels

   weight 3 · round to Unity
   Unity✓fullclaimed9/10

   Unity's Editor is explicitly documented as extendable with custom inspectors, editor windows, and property drawers, backed by scripting APIs and an Asset Database that underpins scene/prefab composition; this is Unity's well-known primary workflow (viewport, inspector, scene/prefab authoring). missing for 10: no direct hands-on/independent walkthrough of prefab workflows or viewport usage specifically, just docs on inspector/editor extension and asset management.

   • [claimed-docs] “Unity lets you extend the editor with your own custom inspectors and Editor Windows and you can define how properties are displayed in the i…”
   • [claimed-docs] “Interacting directly with the public Unity APIs allows for finer control and a greater degree of customization.”
   • [claimed-docs] “The Asset Database stores information about the original source asset files and their imported counterparts to keep the two sets of data in …”
   • [claimed-docs] “Packages deliver a wide range of enhancements to Unity through the Package Manager.”

   proof ↗⚑ flag

   Unreal Engine✓fullcommunity7/10

   Unreal's editor-centric workflow (Blueprints visual scripting, Editor extensions, Asset Manager, Level building/testing via UE Toolbar) is well documented as the primary way to construct levels and gameplay without programmer-only tools, and community comments (comm-3, comm-11, comm-16) corroborate that it's an actual GUI-driven editor experience artists use. missing for 10: explicit documentation naming 'viewport' and 'inspector' panels, and 'prefab' terminology (Unreal uses Blueprint/Actor classes instead) with independent hands-on confirmation of scene-composition workflow specifically for technical artists.

   • [claimed-docs] “provides the ability for designers to use virtually the full range of concepts and tools generally only available to programmers”
   • [claimed-docs] “Plugins can add runtime gameplay functionality, modify built-in Engine features (or add new ones), create new file types, and extend the cap…”
   • [claimed-docs] “provides a framework for managing Assets that can divide content into chunks that make sense in the context of your project”
   • [claimed-docs] “Use UE Toolbar to quickly test a part of your currently loaded Level for testing and debugging.”
   • [community] “Unreal was already the best engine purely on being easy to work with, support from third party programs and community, none of those things …”
   • [community] “What I hate about unity is the whole interface editor thing... Is this Unreal Engine more earth to earth when it comes to programming?”

   proof ↗⚑ flag

Extensibility

1. game developerExtend and automate the editor itself — custom tools, editor scripts, plugins that manipulate scenes and assets programmatically

   weight 3 · round to Unity
   Unity✓fullclaimed9/10

   Unity's docs explicitly document extending the editor with custom inspectors, Editor Windows, Property Drawers, and direct scripting access to public Unity APIs, plus AssetDatabase APIs for programmatic asset manipulation and a Package Manager for distributing/consuming editor tooling — directly matching the story's ask for custom tools/editor scripts/plugins that manipulate scenes and assets. This is a first-party, mature, widely-used capability (also evidenced by a large third-party ecosystem like community MCP tooling built on this extensibility). Missing for 10: independent hands-on developer testimonials specifically about editor scripting workflows (community evidence in the pack focuses on pricing/licensing controversies, not editor extensibility).

   • [claimed-docs] “Unity lets you extend the editor with your own custom inspectors and Editor Windows and you can define how properties are displayed in the i…”
   • [claimed-docs] “Interacting directly with the public Unity APIs allows for finer control and a greater degree of customization.”
   • [claimed-docs] “The Asset Database stores information about the original source asset files and their imported counterparts to keep the two sets of data in …”
   • [claimed-docs] “Packages deliver a wide range of enhancements to Unity through the Package Manager.”

   proof ↗⚑ flag

   Unreal Engine✓fullcommunity8/10

   Docs confirm multiple official extension paths: Python editor scripting for automating asset/editor tasks, Blueprints for designer-level scripting, C++ for deep gameplay/editor class extension, and a Plugins system explicitly designed to 'extend the capabilities of the Editor.' These are core, well-documented first-party mechanisms for programmatic scene/asset manipulation and editor customization. Missing for 10: independent hands-on corroboration specifically of the Python/editor-scripting API (community evidence mostly discusses C++/Blueprint complexity rather than editor automation), and no mention of newer scripting surfaces like the Editor Utility Widgets or Python API depth in third-party sources.

   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”
   • [claimed-docs] “Plugins can add runtime gameplay functionality, modify built-in Engine features (or add new ones), create new file types, and extend the cap…”
   • [claimed-docs] “Plugins are collections of code and data that developers can easily enable or disable within the Editor on a per-project basis.”
   • [claimed-docs] “provides the ability for designers to use virtually the full range of concepts and tools generally only available to programmers”
   • [claimed-docs] “Creating new Gameplay classes in C++, and all changes will be reflected in the Unreal Editor after compiling with either Visual Studio or XC…”
   • [community] “blueprints are great for prototyping, but once you have too much complexity in a BP it can easily cascade inefficiencies to the point it bec…”

   proof ↗⚑ flag

Ci

1. game developerBuild and export the project from the command line, headless, in CI — no human clicking an editor

   weight 3 · round drawn
   Unity✓fullprobed8/10

   Unity officially documents command-line/editor CLI args, headless mode (-batchmode/-nographics), and BuildSettings/build profiles for automated builds, which together enable scripted, non-interactive CI builds; Unity Hub can be installed headlessly via package managers. Missing for 10: no independent hands-on CI pipeline report confirming end-to-end success, and community evidence notes real friction with setting up CI/build servers due to licensing costs.

   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Run the application in headless mode. In this mode, the application doesn’t display anything or accept user input.”
   • [claimed-docs] “Unity can build your application for different platforms with unique build configurations using build profiles in the Unity Editor.”
   • [probe] “official CLI documented at https://docs.unity3d.com/Manual/EditorCommandLineArguments.html”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity Hub installs keylessly from Homebrew (cask unity-hub 3.21.2, 'Management tool for Unity') — the e…”
   • [community] “The extravagant cost of a Unity seat meant we couldn't afford to give anyone except the Unity devs a license... For the same reason, we coul…”

   proof ↗⚑ flag

   Unreal Engine✓fullprobed8/10

   Official docs give concrete CLI commands for headless building/cooking/packaging/deploying a project (UnrealEditor.exe -run=cook, and the build/cook/package/deploy/run automation command), plus a dedicated command-line-arguments reference for scripted/CI use, all without needing to open the editor UI. Missing for 10: independent third-party CI pipeline case study confirming it works end-to-end, and explicit mention of UAT/BuildCookRun tool name or exit-code/scripting integration details.

   • [claimed-docs] “UnrealEditor.exe <GameName or uproject> -run=cook -targetplatform=<Plat1>+<Plat2>”
   • [claimed-docs] “This command can cook content for a platform, package it up into a platform's native format for distribution, deploys it to the device, and …”
   • [claimed-docs] “Command-line Arguments, also called Additional Launch Parameters, customize how the engine runs on startup.”
   • [claimed-docs] “command-line arguments can be an invaluable tool for testing and optimizing your project”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

Server

1. game developerGame logic runs headless on servers — a dedicated-server or server-runtime build without rendering

   weight 2 · round to Unity
   Unity✓fullprobed8/10

   Unity's Player command-line docs explicitly describe running the application in headless mode with no rendering or input, and this combines with documented command-line/batchmode automation for server builds; Unity is widely used to build dedicated-server binaries via this mechanism. Missing for 10: no first-party 'dedicated server build target' walkthrough or independent case study confirming headless server deployment at scale.

   • [claimed-docs] “Run the application in headless mode. In this mode, the application doesn’t display anything or accept user input.”
   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [probe] “official CLI documented at https://docs.unity3d.com/Manual/EditorCommandLineArguments.html”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   The evidence pack covers general networking/replication (client-server sync), command-line arguments, and cooking/packaging, but nowhere mentions Unreal's dedicated-server build target, a headless/no-rendering server runtime, or how to produce a server-only executable. Without explicit documentation of a server-only build path, this axis is unsupported by the given evidence. Missing for 10: any mention of a 'Server' build target, -server or -nullrhi headless launch flags, or dedicated-server packaging instructions.

   • [claimed-docs] “Replication is the name for the process of synchronizing data and procedure calls between clients and servers”
   • [claimed-docs] “Replication is the name for the process of synchronizing data and procedure calls between clients and servers.”
   • [claimed-docs] “UnrealEditor.exe <GameName or uproject> -run=cook -targetplatform=<Plat1>+<Plat2>”
   • [claimed-docs] “This command can cook content for a platform, package it up into a platform's native format for distribution, deploys it to the device, and …”
   • [claimed-docs] “Command-line Arguments, also called Additional Launch Parameters, customize how the engine runs on startup.”

   proof ↗⚑ flag

Testing

1. game developerTests run headlessly — unit and integration tests of game code execute in CI against the real engine

   weight 2 · round to Unity
   Unity~partialcommunity5/10

   Unity docs confirm the Editor/Player can be run headlessly via command-line arguments (-batchmode, -nographics equivalents) which is the foundation for CI automation (unity-docs-6,7,8), and community evidence confirms a CI build server setup is a real (if costly) practice (unity-comm-13). However, there is no direct evidence of Unity's Test Runner/Test Framework CLI flags (e.g., -runTests) or of CI-based unit/integration test execution against the real engine — the pack only shows generic headless launch capability, not test-specific automation. missing for 10: explicit Unity Test Framework / -runTests CLI documentation, evidence of CI pipelines executing engine unit tests, independent hands-on confirmation of headless test runs succeeding.

   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Run the application in headless mode. In this mode, the application doesn’t display anything or accept user input.”
   • [community] “The extravagant cost of a Unity seat meant we couldn't afford to give anyone except the Unity devs a license... For the same reason, we coul…”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   The evidence pack only shows generic command-line argument docs and a UE Toolbar mention for ad-hoc level testing/debugging; there is no evidence of Unreal's Automation System, Gauntlet, or any documented headless unit/integration test execution flow running the real engine in CI. Missing for 10: mention of the Automation Testing framework, -nullrhi/-unattended/-ExecCmds test invocation, CI integration examples, or independent reports of headless test runs against the real engine.

   ⚑ flag

Governance

1. studio leadThe project's governance and funding are transparent — a foundation, published finances, or a public roadmap I can plan against

   weight 1 · round drawn
   Unity—none0/10

   Unity is a commercial, for-profit company with no evidence of foundation governance, published financials, or a public roadmap a studio could plan against; the only related material is marketing pages and a blog post reversing a pricing decision. Community evidence instead documents unilateral, retroactive policy changes (comm-2, comm-7, comm-12, comm-15) that undermine any sense of predictable governance.

   • [claimed-docs] “Unity is Canceling the Runtime Fee”
   • [community] “It reminds me of Darth Vader's line: 'I have altered the deal. Pray I don't alter it further.' The per-install fee applies retroactively to …”
   • [community] “Unity's mishandling of the Runtime Fee policy announcement has caused permanent damage to their reputation. I follow a lot of game developer…”
   • [community] “Unity forced my last company into the more expensive license unilaterally and with no discussion. They doubled our costs just because they c…”
   • [community] “This shows once again that Unity is an unreliable option for new projects. The worst part is not the 4% fee, but the bluntness with which Un…”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   Evidence covers licensing costs, royalty terms, and technical documentation, but nothing indicates a governing foundation, published financial statements, or a public roadmap for Unreal Engine — Epic Games remains a private, closed-governance company with only EULA/royalty terms disclosed (unreal-docs-10, unreal-comm-9, unreal-comm-13).

   • [claimed-docs] “Access to the source code”
   • [community] “For those who don't know what the deal is with Unreal Engine, there's no charge until you get the first million dollars in revenue. Then the…”
   • [community] “It appears they've backed off on the royalties, too: originally, it was 5% of gross, and now it's 5% of gross after $3000 sales per quarter.”

   proof ↗⚑ flag

License

1. studio leadThe license is permissive with no royalties or per-install fees — I keep what my game earns

   weight 3 · round to Unity
   Unity!disputedcontradicted3/10

   Unity's default model is seat/subscription-based (not per-revenue royalties) and the controversial per-install Runtime Fee was announced and then canceled (unity-docs-21), which superficially supports 'no royalties/per-install fees.' However, concrete community evidence directly contradicts the 'permissive, keep what you earn' framing: the per-install fee was retroactively applied to already-shipped games before cancellation (unity-comm-2), studios report being unilaterally forced into pricier license tiers (unity-comm-12), and developers describe Unity's terms as able to 'change at any moment' (unity-comm-15) — the opposite of a stable, low-friction license. missing for 10: vendor documentation of the actual current licensing terms/royalty structure, resolution confirming no future fee reintroduction, and independent legal/financial analysis of the license's permissiveness.

   • [claimed-docs] “Unity is Canceling the Runtime Fee”
   • [community] “It reminds me of Darth Vader's line: 'I have altered the deal. Pray I don't alter it further.' The per-install fee applies retroactively to …”
   • [community] “Unity forced my last company into the more expensive license unilaterally and with no discussion. They doubled our costs just because they c…”
   • [community] “This shows once again that Unity is an unreliable option for new projects. The worst part is not the 4% fee, but the bluntness with which Un…”
   • [community] “Unity's mishandling of the Runtime Fee policy announcement has caused permanent damage to their reputation. I follow a lot of game developer…”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   Community evidence explicitly documents that Unreal charges a 5% royalty on gross revenue after the first $1M (or $3,000/quarter) — this is the opposite of 'no royalties, keep what you earn.' No evidence pack item supports a royalty-free/no-fee licensing model; instead multiple citations (comm-1, comm-9, comm-13, comm-2) confirm a royalty-based commercial license.

   • [community] “UE offers everything free... Only way to pay to use Unreal Engine is to earn more than $1,000,000 USD which for most people means everything…”
   • [community] “For those who don't know what the deal is with Unreal Engine, there's no charge until you get the first million dollars in revenue. Then the…”
   • [community] “It appears they've backed off on the royalties, too: originally, it was 5% of gross, and now it's 5% of gross after $3000 sales per quarter.”
   • [community] “i know games with $3 million dollar budgets that chose Unity over Unreal because with Unreal that would have cost them $150k whereas with Un…”

   proof ↗⚑ flag

Source

1. game developerRead and modify the full engine source when I hit a wall

   weight 2 · round to Unreal Engine
   Unity—none0/10

   Evidence covers scripting APIs, editor extensibility, and packages, but nothing indicates access to or modification of Unity's actual engine source code (Unity is closed-source/proprietary); community evidence instead highlights licensing rigidity and forced fee changes, reinforcing lack of source openness. Missing for 10: any documentation of source code licenses, C++ engine source access program, or ability to recompile/modify the core engine.

   • [claimed-docs] “Unity lets you extend the editor with your own custom inspectors and Editor Windows and you can define how properties are displayed in the i…”
   • [claimed-docs] “Interacting directly with the public Unity APIs allows for finer control and a greater degree of customization.”
   • [community] “Unity forced my last company into the more expensive license unilaterally and with no discussion. They doubled our costs just because they c…”
   • [community] “The extravagant cost of a Unity seat meant we couldn't afford to give anyone except the Unity devs a license... For the same reason, we coul…”

   proof ↗⚑ flag

   Unreal Engine✓fullprobed7/10

   Epic's license page explicitly grants 'Access to the source code' and docs describe creating new Gameplay C++ classes that recompile directly into the Editor, and community comments corroborate 'source code included.' Missing for 10: independent hands-on account of actually patching core engine internals (not just gameplay classes), and the probe notes the source repo is EULA/GitHub-account gated rather than freely open, which adds friction to the 'when I hit a wall' scenario.

   • [claimed-docs] “Access to the source code”
   • [claimed-docs] “Access to the source code All platforms & features Forums and documentation on the Epic Developer Community”
   • [claimed-docs] “Creating new Gameplay classes in C++, and all changes will be reflected in the Unreal Editor after compiling with either Visual Studio or XC…”
   • [claimed-docs] “Creating new Gameplay classes in C++, and all changes will be reflected in the Unreal Editor after compiling with either Visual Studio or XC…”
   • [community] “Crytek has financial worries. Plus it's the most difficult to use, because it's almost all C++. Unity is very accessible thanks to C# script…”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

Trust

1. studio leadThe pricing and license terms have a track record of stability — no retroactive changes that reprice games already shipped

   weight 2 · round drawn
   Unity—none0/10

   Community evidence directly documents a retroactive pricing change (the 2023 Runtime Fee applied to already-shipped games) and multiple accounts of unilateral license/cost changes forced on existing customers, the opposite of the stability this story asks for; no vendor commitment to non-retroactive pricing is evidenced.

   • [community] “It reminds me of Darth Vader's line: 'I have altered the deal. Pray I don't alter it further.' The per-install fee applies retroactively to …”
   • [community] “Unity forced my last company into the more expensive license unilaterally and with no discussion. They doubled our costs just because they c…”
   • [community] “This shows once again that Unity is an unreliable option for new projects. The worst part is not the 4% fee, but the bluntness with which Un…”
   • [claimed-docs] “Unity is Canceling the Runtime Fee”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   The pack shows royalty terms changed over time (5% of gross → 5% after $3,000/quarter) but no evidence addresses whether such changes were ever applied retroactively to already-shipped titles or whether Epic has an explicit no-retroactive-repricing policy/track record. Missing for 10: documented policy or community confirmation that license terms are grandfathered for shipped games, evidence of any past retroactive-change controversy or its resolution.

   • [community] “It appears they've backed off on the royalties, too: originally, it was 5% of gross, and now it's 5% of gross after $3000 sales per quarter.”
   • [community] “For those who don't know what the deal is with Unreal Engine, there's no charge until you get the first million dollars in revenue. Then the…”
   • [claimed-docs] “Access to the source code”

   proof ↗⚑ flag

1. ai-native userDo everything through the API that I can do in the UI

   weight 2 · round drawn
   Unity~partialprobed5/10

   Unity exposes extensive scripting APIs, editor extensibility, and CLI/command-line automation for builds and headless runs, letting many UI workflows be scripted, but there is no general REST/GraphQL API mirroring the full Editor UI — automation is Editor/CLI/C#-script based rather than a universal API surface, and no OpenAPI spec exists (404s confirmed). missing for 10: a documented general-purpose API (not just CLI args/C# scripting) covering all UI actions, evidence of parity between UI and programmatic access, and confirmation openapi/swagger specs exist.

   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Run the application in headless mode. In this mode, the application doesn’t display anything or accept user input.”
   • [claimed-docs] “Unity lets you extend the editor with your own custom inspectors and Editor Windows and you can define how properties are displayed in the i…”
   • [claimed-docs] “Interacting directly with the public Unity APIs allows for finer control and a greater degree of customization.”
   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.unity3d.com/openapi.json, https://docs.unity3d.com/swagger.json, https://docs.unity3d.c…”
   • [probe] “official CLI documented at https://docs.unity3d.com/Manual/EditorCommandLineArguments.html”

   proof ↗⚑ flag

   Unreal Engine~partialprobed5/10

   Unreal exposes substantial programmatic surfaces (Python editor scripting, C++ gameplay/engine API, Blueprints, command-line/UAT automation) that cover many editor and runtime tasks, but there is no documentation or evidence claiming full UI/API parity — some editor UI workflows (e.g. certain asset browser, viewport, or complex tooling operations) are not confirmed as scriptable, and the probe notes the engine is poorly machine-accessible overall (gated source repo, 403s on core domains, no official MCP, docs not served as markdown). missing for 10: an explicit statement/spec of full UI-API parity, evidence that every UI action has an API equivalent, and better machine-readable API discovery for AI agents.

   • [claimed-docs] “provides the ability for designers to use virtually the full range of concepts and tools generally only available to programmers”
   • [claimed-docs] “Automate time-consuming Asset management tasks in the Unreal Editor, like generating Levels of Detail (LODs) for Static Meshes.”
   • [claimed-docs] “there may be cases where you want precise control over when and how Assets are discovered, loaded, and audited. For these cases, the Asset M…”
   • [claimed-docs] “Creating new Gameplay classes in C++, and all changes will be reflected in the Unreal Editor after compiling with either Visual Studio or XC…”
   • [claimed-docs] “command-line arguments can be an invaluable tool for testing and optimizing your project”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

2. ai-native userExport all of my data in open formats and leave

   weight 3 · round drawn
   Unity—none0/10

   The evidence pack contains no documentation of a data-export feature or open-format portability guarantee for Unity projects (assets, scenes, or AI credits data); most content is about platform support, editor extensibility, and pricing controversies, not data portability.

   ⚑ flag

   Unreal Engine—none0/10

   Evidence covers Blueprints, C++, plugins, source-code access, and asset management, but nothing addresses exporting a project's proprietary .uasset/.umap data into open interchange formats to allow a clean migration away from Unreal. The probe evidence even highlights poor machine-readable/open access to Epic's own ecosystem, reinforcing the lack of a data-portability story.

   • [claimed-docs] “provides a framework for managing Assets that can divide content into chunks that make sense in the context of your project”
   • [claimed-docs] “there may be cases where you want precise control over when and how Assets are discovered, loaded, and audited. For these cases, the Asset M…”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

3. ai-native userRead the product's source under an open license

   weight 2 · round to Unreal Engine
   Unity—none0/10

   Unity Engine is proprietary; there is no evidence of an open-source license for its source code, and Unity is a closed commercial product per the evidence (Package Manager, paid plans, closed MCP distribution). This is a fair axis to ask of any dev platform, but no evidence supports open-source availability of Unity's source.

   • [claimed-docs] “Packages deliver a wide range of enhancements to Unity through the Package Manager.”
   • [claimed-docs] “Unity’s free plan, Unity Personal, is for individuals and small organizations with less than $100K of revenue and funds raised in the last 1…”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity ships an OFFICIAL MCP server as part of Unity's AI tools (beta) inside the com.unity.ai.assistant…”

   proof ↗⚑ flag

   Unreal Engine!disputedcontradicted3/10

   Epic's own licensing page claims 'access to the source code' (unreal-docs-10, unreal-docs-18), but this is EULA/account-gated rather than an open-license grant — the probe confirms the GitHub source repo returns 404 without an authenticated, linked Epic account and all first-party domains block non-browser access, meaning the source is not freely readable under an open license as an AI-native user would need. Missing for 10: no OSI-approved or otherwise open license governing the source, no keyless/anonymous access to the code, no llms.txt or machine-readable confirmation of licensing terms.

   • [claimed-docs] “Access to the source code”
   • [claimed-docs] “Access to the source code All platforms & features Forums and documentation on the Epic Developer Community”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

4. ai-native userSelf-host the core product

   weight 3 · round drawn
   Unity~partialprobed6/10

   Unity's core Editor/Player is inherently installed and run on the user's own machines (Unity Hub installs locally, headless -batchmode/-nographics CLI for CI build servers, EditorCommandLineArguments for automation), so the core engine is effectively self-hosted by design rather than a vendor-controlled cloud service. However, Unity's newer AI-native features (Unity AI Assistant, MCP integration) are explicitly cloud-metered via Unity Credits with no public/self-hostable package, so the AI-native layer itself cannot be self-hosted. Missing for 10: a documented self-hosted deployment path for the AI/MCP layer, and any first-party guidance on self-hosting build infrastructure at scale (e.g. license/build-server constraints noted in community reports).

   • [claimed-docs] “You can run the Unity Editor and Players from command-line interfaces to change and customize how they run at launch time.”
   • [claimed-docs] “You can launch the Unity Editor and Player with additional command line arguments to control startup behavior, configure settings, or automa…”
   • [claimed-docs] “Run the application in headless mode. In this mode, the application doesn’t display anything or accept user input.”
   • [claimed-docs] “Unity can build your application for different platforms with unique build configurations using build profiles in the Unity Editor.”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity ships an OFFICIAL MCP server as part of Unity's AI tools (beta) inside the com.unity.ai.assistant…”
   • [probe] “PROBE runtime (recorded 2026-09-15): Unity Hub installs keylessly from Homebrew (cask unity-hub 3.21.2, 'Management tool for Unity') — the e…”
   • [community] “The extravagant cost of a Unity seat meant we couldn't afford to give anyone except the Unity devs a license... For the same reason, we coul…”

   proof ↗⚑ flag

   Unreal Engine~partialprobed6/10

   Unreal ships as a locally-installed engine with source-code access (unreal-docs-10/18), so the core product is inherently self-hostable rather than SaaS-only. However, the probe evidence shows source access is EULA/account-gated (must link a GitHub account to Epic), the GitHub repo is not publicly discoverable via API, and there is no simple open self-hosting path comparable to fully open-source engines. Missing for 10: unrestricted/public source access, no account-gating requirement, first-party documentation framing self-hosting as an explicit feature.

   • [claimed-docs] “Access to the source code”
   • [claimed-docs] “Access to the source code All platforms & features Forums and documentation on the Epic Developer Community”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): Unreal is the least machine-readable presence of the eight — api.github.com/repos/EpicGames/Un…”

   proof ↗⚑ flag

Targets

1. studio leadOne project exports to desktop, mobile, and (directly or via partners) consoles

   weight 3 · round to Unity
   Unity✓fullclaimed8/10

   Unity's docs explicitly advertise building for 25+ platforms including desktop, mobile, and consoles via build profiles/Build Settings, and it is well established that console export happens through Unity's console-partner program rather than open SDKs. Missing for 10: no direct evidence pack detail on console-specific partner workflow/certification process or independent studio confirmation of simultaneous multi-platform shipping.

   • [claimed-docs] “Build 2D and 3D games for any platform”
   • [claimed-docs] “Discover 25+ platforms Unity supports”
   • [claimed-docs] “Unity can build your application for different platforms with unique build configurations using build profiles in the Unity Editor.”
   • [claimed-docs] “Ship big games with small teams”

   proof ↗⚑ flag

   Unreal Engine~partialcommunity7/10

   Docs show a single project can be cooked/packaged/deployed to multiple target platforms via the cook/package pipeline (unreal-docs-16, unreal-docs-17) and tested across platforms via the toolbar (unreal-docs-9), and community mentions cross-platform export (e.g., HTML5) confirm this in practice (unreal-comm-14). However, the evidence pack contains no explicit documentation or independent confirmation of console export specifics (partner/licensee console SDK integration), so console support is inferred rather than directly evidenced. Missing for 10: explicit console-platform export/partner-program documentation, independent studio confirmation of a single project shipping to consoles.

   • [claimed-docs] “UnrealEditor.exe <GameName or uproject> -run=cook -targetplatform=<Plat1>+<Plat2>”
   • [claimed-docs] “This command can cook content for a platform, package it up into a platform's native format for distribution, deploys it to the device, and …”
   • [claimed-docs] “Use UE Toolbar to quickly test a part of your currently loaded Level for testing and debugging.”
   • [community] “For someone who's actually using UE4 as an artistic break for web dev, I thoroughly recommend it. It allows you to create great environments…”

   proof ↗⚑ flag

Web

1. web developerMy game runs in the browser with a reasonable payload — WebGL today, and a credible WebGPU story

   weight 2 · round drawn
   Unity—none0/10

   The evidence pack only offers generic cross-platform claims (e.g., '25+ platforms', 'any platform') with no mention of WebGL, WebGPU, browser payload size, or any web-specific export tooling; nothing addresses this story's specific subject.

   ⚑ flag

   Unreal Engine—none0/10

   The only evidence touching web export is a decade-old community comment noting 'UE4.7 can export to HTML5 too' (unreal-comm-14) — there is no current documentation, no mention of WebGL, no mention of WebGPU, and no discussion of browser payload size or a credible modern web-export pipeline. Given Unreal actually removed HTML5/WebGL export in later versions, this stale anecdote does not establish a current capability.

   • [community] “For someone who's actually using UE4 as an artistic break for web dev, I thoroughly recommend it. It allows you to create great environments…”

   proof ↗⚑ flag

2. web developerThe engine installs from a package registry into my existing toolchain — a library I import, bundle, and tree-shake like any dependency

   weight 2 · round drawn
   Unity—none0/10

   The axis applies to this product kind (peer products hold positive or none verdicts on this story), so lack of evidence for an applicable capability is "none", never "na". (na/none harmonized at arena bring-up — see pipeline/scripts/na-harmonize.ts.)

   ⚑ flag

   Unreal Engine—none0/10

   The axis applies to this product kind (peer products hold positive or none verdicts on this story), so lack of evidence for an applicable capability is "none", never "na". (na/none harmonized at arena bring-up — see pipeline/scripts/na-harmonize.ts.)

   ⚑ flag

1. ai-native userOpt out of telemetry and usage tracking

   weight 2 · round drawn
   Unity—none0/10

   No evidence pack item documents a telemetry opt-out setting or privacy control for Unity; the only related evidence is a community complaint about unwanted 'phone home' logging (unity-comm-14), which if anything suggests telemetry behavior was hard to avoid rather than confirming an opt-out mechanism exists.

   • [community] “I switched to unreal several years ago because Unity had written hundreds of gigabytes of log files complaining that it could not phone home…”

   proof ↗⚑ flag

   Unreal Engine—none0/10

   No evidence in the pack addresses telemetry, analytics, or usage-tracking opt-out settings for Unreal Engine or the Editor; all docs and community items concern scripting, licensing, and pricing topics unrelated to privacy controls.

   ⚑ flag

Iteration

1. game developerThe edit-run loop is fast — hot reload or near-instant preview after a script change

   weight 2 · round to Unreal Engine
   Unity—none0/10

   The evidence pack covers scripting APIs, editor extensibility, CLI/build automation, and packages, but contains no documentation or community evidence specifically about hot reload, domain reload speed, or near-instant preview after script changes — a well-known pain point/feature area for Unity that simply isn't addressed here.

   ⚑ flag

   Unreal Engine~partialclaimed6/10

   Docs confirm Blueprints allow instant in-editor scripting changes without recompilation, and C++ changes are 'reflected in the Unreal Editor after compiling' via Visual Studio/XCode, indicating a hot-reload/live-coding workflow exists. However, no evidence quantifies compile/reload speed, mentions the dedicated 'Live Coding' feature explicitly, or provides independent hands-on confirmation that the loop is fast rather than just functional. Missing for 10: benchmark/timing evidence on hot reload speed, explicit mention of Live Coding feature, independent developer testimony on edit-run loop responsiveness.

   • [claimed-docs] “provides the ability for designers to use virtually the full range of concepts and tools generally only available to programmers”
   • [claimed-docs] “Creating new Gameplay classes in C++, and all changes will be reflected in the Unreal Editor after compiling with either Visual Studio or XC…”
   • [claimed-docs] “Creating new Gameplay classes in C++, and all changes will be reflected in the Unreal Editor after compiling with either Visual Studio or XC…”

   proof ↗⚑ flag

Language

1. game developerThe primary scripting language is productive and fully exposes the engine API, with a debugger behind it

   weight 3 · round to Unreal Engine
   Unity~partialcommunity4/10

   Evidence confirms Unity exposes public scripting APIs directly for fine-grained control and customization (unity-docs-11), and community comments corroborate that C# scripting is product993 and lets devs 'ignore the engine features' (unity-comm-4), supporting productivity. However, there is no evidence in the pack about a debugger being available or integrated for the scripting language, nor any detail on API completeness/coverage. Missing for 10: documentation or corroboration of a debugger (breakpoints, step-through, attach-to-process) for the scripting workflow, and evidence of full API surface coverage beyond general scripting docs.

   • [claimed-docs] “Interacting directly with the public Unity APIs allows for finer control and a greater degree of customization.”
   • [community] “I used XNA, then MS killed it... then switched to Unity, been using it since 2012... As a lone indie dev I find Unreal very tedious and slow…”

   proof ↗⚑ flag

   Unreal Engine~partialcommunity5/10

   Docs show C++ as the primary language with full engine API exposure (new Gameplay classes, delegates binding to arbitrary objects) and it compiles/reflects via Visual Studio/XCode, implying standard IDE debugger support, while Blueprints (the more 'scripting'-like option) explicitly trades off some API depth for accessibility (unreal-docs-1,2,3,11). Community evidence corroborates a productivity/API-completeness tension: Blueprints alone are 'not sufficient' for real scripting tasks and require C++ fallback, and multiple developers cite C++ as their 'main problem' with UE (unreal-comm-4, unreal-comm-7, unreal-comm-15). Missing for 10: no explicit documentation of an integrated scripting debugger workflow (only external Visual Studio/Xcode debugging is implied), and no first-party evidence that any single primary language achieves both full productivity and full API coverage without trade-offs.

   • [claimed-docs] “provides the ability for designers to use virtually the full range of concepts and tools generally only available to programmers”
   • [claimed-docs] “Creating new Gameplay classes in C++, and all changes will be reflected in the Unreal Editor after compiling with either Visual Studio or XC…”
   • [claimed-docs] “You can dynamically bind a delegate to a member function of an arbitrary object, calling the function on the object at a future time”
   • [claimed-docs] “Creating new Gameplay classes in C++, and all changes will be reflected in the Unreal Editor after compiling with either Visual Studio or XC…”
   • [community] “With no scripting support, adding content like vehicles is pretty much impossible. Blueprints are not sufficient for such a task. A few peop…”
   • [community] “My main problem with UE is C++, I don't want to even try to download files or read json in a blueprint.”
   • [community] “blueprints are great for prototyping, but once you have too much complexity in a BP it can easily cascade inefficiencies to the point it bec…”

   proof ↗⚑ flag

Visual

1. technical artistBuild gameplay logic with visual scripting without writing code

   weight 2 · round to Unreal Engine
   Unity—none0/10

   The evidence pack contains no mention of Unity's Visual Scripting tool (or any no-code/node-based logic system) — it only documents C# scripting, editor extension APIs, and command-line tooling. Missing for 10: any documentation of a visual/node-based scripting system, tutorials or community proof of technical artists building gameplay logic without code.

   ⚑ flag

   Unreal Engine!disputedcontradicted6/10

   Epic's docs confirm Blueprints let designers use most programmer-level tools without code (unreal-docs-1), and this is Unreal's flagship visual-scripting system for gameplay logic. However, hands-on community reports concretely contradict full no-code sufficiency: one dev states Blueprints were 'not sufficient' for adding content like vehicles and required C++ (unreal-comm-4), and another notes complex Blueprint graphs 'cascade inefficiencies' making C++ necessary at scale (unreal-comm-15), with a third citing C++ as the main pain point when trying to avoid it (unreal-comm-7). Missing for 10: independent case studies of large shipped games built purely in Blueprints without C++ fallback, and clearer scoping of what gameplay complexity Blueprints alone can handle.

   • [claimed-docs] “provides the ability for designers to use virtually the full range of concepts and tools generally only available to programmers”
   • [community] “With no scripting support, adding content like vehicles is pretty much impossible. Blueprints are not sufficient for such a task. A few peop…”
   • [community] “blueprints are great for prototyping, but once you have too much complexity in a BP it can easily cascade inefficiencies to the point it bec…”
   • [community] “My main problem with UE is C++, I don't want to even try to download files or read json in a blueprint.”

   proof ↗⚑ flag