Bevy vs PlayCanvas

Agent access

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

   weight 2 · round to PlayCanvas
   Bevy—none0/10

   Direct probes confirm no llms.txt exists (404) and no agent-oriented docs endpoint is served; docs.rs/crates.io provide standard human docs but nothing tailored for agent consumption per the story.

   • [probe] “PROBE llms.txt: HTTP 404 at https://bevy.org/llms.txt”
   • [probe] “PROBE docs-md: HTTP 404 at https://bevy.org/learn/.md”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): bevy.org serves no llms.txt (HTTP 404; docs.rs likewise) and no official MCP exists — communit…”

   proof ↗⚑ flag

   PlayCanvas✓fullprobed9/10

   A working llms.txt confirmed via HTTP 200 probe plus an unusually large llms-full.txt (2MB) of complete docs is directly served at developer.playcanvas.com, satisfying the exact story of pointing an agent at llms.txt/agent-oriented docs. This is corroborated by both docs claims and independent runtime probes, not just vendor assertion. Missing for 10: no independent third-party (non-probe) report of an agent actually consuming the file successfully in a real workflow.

   • [probe] “PROBE llms.txt: HTTP 200 at https://developer.playcanvas.com/llms.txt # PlayCanvas Developer Documentation > PlayCanvas is an open-source W…”
   • [probe] “PROBE runtime (recorded 2026-09-15): developer.playcanvas.com serves llms.txt plus the largest llms-full.txt of the arena (2,053,637 bytes o…”

   proof ↗⚑ flag

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

   weight 2 · round drawn
   Bevy—none0/10

   The evidence pack contains no mention of headless mode, CI integration, or automated/scripted execution of Bevy apps; only rendering, ECS, editor-live-reload and general community sentiment are covered. Running headless in CI is a reasonable ask for a game engine, but nothing in the pack demonstrates it.

   ⚑ flag

   PlayCanvas—none0/10

   Evidence shows the engine is npm-installable and there's an Editor MCP server, but the MCP server explicitly requires 'an open PlayCanvas Editor session' (interactive), and no evidence describes headless rendering, CI pipelines, or server-side/automated execution of the engine or editor without a live browser/editor session.

   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [github] “npm install playcanvas”
   • [community] “When I was working at a mobile game studio, we looked at this as an engine for a project. At the time we decided not to go with it since all…”

   proof ↗⚑ flag

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

   weight 3 · round to PlayCanvas
   Bevy—none0/10

   Bevy is a game engine/library, not itself an AI agent, so an MCP server axis applies as a fair question, but evidence explicitly shows no official MCP server exists — only nascent third-party tooling (bevy_brp) built on the Bevy Remote Protocol. No official MCP server is documented.

   • [probe] “PROBE runtime negative (recorded 2026-09-15): bevy.org serves no llms.txt (HTTP 404; docs.rs likewise) and no official MCP exists — communit…”
   • [probe] “PROBE llms.txt: HTTP 404 at https://bevy.org/llms.txt”

   proof ↗⚑ flag

   PlayCanvas✓fullprobed9/10

   PlayCanvas documents and ships an official, first-party MCP server (`@playcanvas/editor-mcp-server`, npm-published, official org repo) that connects AI assistants to a live Editor session to modify project data and verify results via the viewport, confirmed both in docs and runtime probes. Missing for 10: independent third-party hands-on validation of the MCP server beyond vendor docs/probe.

   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [probe] “official MCP server documented at https://developer.playcanvas.com/user-manual/editor/mcp-server/”
   • [probe] “PROBE runtime (recorded 2026-09-15): PlayCanvas ships the only OFFICIAL, open, npm-published editor MCP server of the eight engines — `npm v…”

   proof ↗⚑ flag

4. ai-native userUse an official CLI

   weight 2 · round to PlayCanvas
   Bevy—none0/10

   No evidence of an official Bevy CLI tool anywhere in the evidence pack; only cargo (Rust's generic build tool) and community projects like bevy_brp are mentioned, not a first-party CLI for AI-native workflows.

   ⚑ flag

   PlayCanvas~partialclaimed4/10

   PlayCanvas ships an official `create-playcanvas` CLI for scaffolding Vite/TypeScript projects, which an AI agent could invoke, but the docs describe it purely as a project scaffolder with no explicit AI-native/agentic features (non-interactive flags, scripting API, automation hooks) and no independent confirmation of agent usage. Missing for 10: documentation of CLI flags/JSON output for automation, evidence of AI-agent usage, and any tie-in with the MCP server workflow.

   • [claimed-docs] “Use `create-playcanvas` to scaffold a Vite and TypeScript project for the Engine, React, or Web Components from one of 12 runnable starters.”

   proof ↗⚑ flag

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

   weight 3 · round to PlayCanvas
   Bevy~partialprobed5/10

   Bevy ships a documented Rust API (in-depth reference docs, docs.rs) and even a first-party 'Bevy Remote Protocol' that a nascent community tool (bevy_brp) uses to drive the engine externally, but there is no AI-oriented public API surface: no llms.txt, no OpenAPI/swagger spec, and no official MCP server, and the remote-protocol tooling is described as nascent/community-only rather than a robust public API for programmatic driving. Missing for 10: an official machine-readable API spec (OpenAPI/llms.txt), first-party remote-control docs beyond community wrappers, and evidence of stable AI-agent usage against the API.

   • [claimed-docs] “Learn how to use Bevy's types, traits and methods using the in-depth reference documentation, complete with inline examples.”
   • [probe] “PROBE llms.txt: HTTP 404 at https://bevy.org/llms.txt”
   • [probe] “PROBE openapi: all candidate paths 404 (https://bevy.org/openapi.json, https://bevy.org/swagger.json, https://bevy.org/api/openapi.json, htt…”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): bevy.org serves no llms.txt (HTTP 404; docs.rs likewise) and no official MCP exists — communit…”

   proof ↗⚑ flag

   PlayCanvas✓fullprobed7/10

   PlayCanvas exposes a documented scriptable Editor API for automating/customizing the Editor environment (api.playcanvas.com/editor/) plus an official, npm-published Editor MCP Server explicitly built for AI assistants to modify project data and verify results, alongside a standalone Engine API and llms.txt docs for AI consumption. This gives AI-native users multiple documented, programmatic ways to drive the product. Missing for 10: a formal OpenAPI/REST spec (probe found only 404s for openapi/swagger endpoints) and independent third-party confirmation of API-driven automation success.

   • [claimed-docs] “This module is essential for developers looking to streamline their workflow, create custom editing tools, or integrate external data and sy…”
   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [claimed-docs] “Build applications against the Engine directly. Learn how to use the Engine standalone.”
   • [probe] “PROBE runtime (recorded 2026-09-15): PlayCanvas ships the only OFFICIAL, open, npm-published editor MCP server of the eight engines — `npm v…”
   • [probe] “PROBE openapi: all candidate paths 404 (https://developer.playcanvas.com/openapi.json, https://developer.playcanvas.com/swagger.json, https:…”
   • [probe] “PROBE runtime (recorded 2026-09-15): developer.playcanvas.com serves llms.txt plus the largest llms-full.txt of the arena (2,053,637 bytes o…”

   proof ↗⚑ flag

6. ai-native userBuild against official SDKs

   weight 2 · round to PlayCanvas
   Bevy~partialprobed6/10

   Bevy itself ships as an official, versioned Rust SDK (the `bevy` crate on crates.io) with first-party API reference docs, quick-start guides, and migration guides, which is what an AI-native developer would build against (bevy-docs-21, bevy-docs-27, bevy-docs-15, bevy-probe-rt-1). However, pre-1.0 status with breaking changes on nearly every release, community complaints about docs being thin once you leave the intro book, and confirmed absence of llms.txt/AI-consumable doc formats make it harder for AI agents to reliably target the 'official SDK' surface (bevy-probe-rt-1, bevy-comm-12, bevy-comm-14, bevy-probe-1, bevy-probe-rt-2). Missing for 10: llms.txt/AI-friendly doc export, stability guarantees across versions, and independent evidence of AI agents successfully building against the SDK.

   • [claimed-docs] “Bevy is just a normal Rust dependency. You can either add it to an existing Rust project or create a new one.”
   • [claimed-docs] “Learn how to use Bevy's types, traits and methods using the in-depth reference documentation, complete with inline examples.”
   • [claimed-docs] “Every Bevy update brings new functionality and improvements. Follow these guides to migrate your project to the latest Bevy has to offer!”
   • [probe] “PROBE runtime (recorded 2026-09-15): bevy resolves on crates.io — `cargo search bevy` → 'bevy = "0.19.1" # A refreshingly simple data-driven…”
   • [community] “Things have started to stabilize, but unless you're willing to get your hands dirty and deal with regular breaking changes, I don't yet reco…”
   • [community] “I'm put off by the limited docs. I've read the Bevy book, only takes a few minutes, and just like that I'm out of resources to turn to when …”
   • [probe] “PROBE llms.txt: HTTP 404 at https://bevy.org/llms.txt”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): bevy.org serves no llms.txt (HTTP 404; docs.rs likewise) and no official MCP exists — communit…”

   proof ↗⚑ flag

   PlayCanvas✓fullprobed8/10

   PlayCanvas publishes multiple official SDKs — the core Engine (npm `playcanvas`), React and Web Components bindings, a `create-playcanvas` scaffolding CLI, a scriptable Editor API, and an official npm-published Editor MCP server for AI automation — all documented and runtime-verified. Community discussion confirms it integrates with standard JS/React workflows, though it also notes some dev-experience friction unrelated to SDK availability. Missing for 10: independent hands-on developer reports specifically validating SDK usage/quality, and a public OpenAPI/versioned reference (probe found only 404s for openapi.json).

   • [claimed-docs] “Use `create-playcanvas` to scaffold a Vite and TypeScript project for the Engine, React, or Web Components from one of 12 runnable starters.”
   • [claimed-docs] “Build applications against the Engine directly. Learn how to use the Engine standalone.”
   • [claimed-docs] “This module is essential for developers looking to streamline their workflow, create custom editing tools, or integrate external data and sy…”
   • [claimed-docs] “Already use React, want declarative 3D scenes, or need to integrate 3D into React apps”
   • [github] “npm install playcanvas”
   • [probe] “PROBE runtime (recorded 2026-09-15): PlayCanvas ships the only OFFICIAL, open, npm-published editor MCP server of the eight engines — `npm v…”
   • [probe] “PROBE runtime (recorded 2026-09-15): developer.playcanvas.com serves llms.txt plus the largest llms-full.txt of the arena (2,053,637 bytes o…”
   • [community] “You can use it in conjunction with pretty much any other JS framework available.”

   proof ↗⚑ flag

Agentic features

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

   weight 2 · round to PlayCanvas
   Bevy—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

   PlayCanvas~partialprobed4/10

   PlayCanvas ships an official Editor MCP server that lets connected AI assistants read and modify project data and verify results in the viewport, which could be used to generate suggestions/insights from a user's scene data, but there is no evidence of a native, built-in AI insights/recommendations feature (e.g., analytics, optimization suggestions) inside the product itself. Missing for 10: dedicated AI-insights UI or documented use-case of the MCP server producing analytical suggestions, independent corroboration of this workflow in practice.

   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [probe] “official MCP server documented at https://developer.playcanvas.com/user-manual/editor/mcp-server/”
   • [probe] “PROBE runtime (recorded 2026-09-15): PlayCanvas ships the only OFFICIAL, open, npm-published editor MCP server of the eight engines — `npm v…”

   proof ↗⚑ flag

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

   weight 2 · round to PlayCanvas
   Bevy—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

   PlayCanvas~partialprobed4/10

   PlayCanvas ships an official Editor MCP server that lets AI assistants programmatically modify project data, but it explicitly requires 'an open PlayCanvas Editor session' rather than running as an independent, scheduled, or background process — this is closer to AI-assisted live editing than autonomous background automation. Missing for 10: evidence of scheduled/triggered jobs, headless/background execution without a live editor session, or any autonomous agent loop running unattended.

   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [probe] “official MCP server documented at https://developer.playcanvas.com/user-manual/editor/mcp-server/”
   • [probe] “PROBE runtime (recorded 2026-09-15): PlayCanvas ships the only OFFICIAL, open, npm-published editor MCP server of the eight engines — `npm v…”

   proof ↗⚑ flag

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

   weight 3 · round to PlayCanvas
   Bevy—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

   PlayCanvas~partialprobed5/10

   PlayCanvas does not ship a built-in AI assistant embedded in its UI; instead it exposes an official Editor MCP server that lets external AI assistants (e.g. Claude) connect to an open Editor session and modify/inspect project data via the viewport, effectively allowing task delegation to AI, but the assistant itself lives outside the product rather than inside it. Missing for 10: a first-party, in-product AI assistant UI/chat surface, and any hands-on/community verification that delegation via MCP works well in practice.

   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [probe] “official MCP server documented at https://developer.playcanvas.com/user-manual/editor/mcp-server/”
   • [probe] “PROBE runtime (recorded 2026-09-15): PlayCanvas ships the only OFFICIAL, open, npm-published editor MCP server of the eight engines — `npm v…”

   proof ↗⚑ flag

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

   weight 2 · round to PlayCanvas
   Bevy—none0/10

   Bevy is a Rust game engine/library with no evidence of any natural-language command interface; probes confirm no llms.txt, no MCP server, and only nascent third-party remote-protocol tooling (bevy_brp), not a natural-language control layer.

   • [probe] “PROBE llms.txt: HTTP 404 at https://bevy.org/llms.txt”
   • [probe] “PROBE docs-md: HTTP 404 at https://bevy.org/learn/.md”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): bevy.org serves no llms.txt (HTTP 404; docs.rs likewise) and no official MCP exists — communit…”

   proof ↗⚑ flag

   PlayCanvas~partialprobed6/10

   PlayCanvas ships an official, npm-published Editor MCP Server that lets AI assistants modify project data and verify results via the viewport, which is a genuine natural-language/agentic control surface for the Editor. However, this only covers Editor operations, not the runtime Engine or broader workflows, and there's no independent/hands-on evidence of it being used successfully in practice. missing for 10: community/hands-on validation of the MCP server in real workflows, evidence of natural-language control over the Engine/runtime (not just Editor), and broader agentic tool coverage beyond the single MCP server.

   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [probe] “official MCP server documented at https://developer.playcanvas.com/user-manual/editor/mcp-server/”
   • [probe] “PROBE runtime (recorded 2026-09-15): PlayCanvas ships the only OFFICIAL, open, npm-published editor MCP server of the eight engines — `npm v…”

   proof ↗⚑ flag

Api quality

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

   weight 2 · round to Bevy
   Bevy~partialprobed5/10

   Bevy advertises 'in-depth reference documentation, complete with inline examples' and a separate gallery of wasm-compiled examples that run directly in the browser, giving some interactive/runnable exploration of the API surface. But these are two disconnected resources rather than a unified interactive API reference, docs.rs is static/crawlable with no live-run capability, and there's no llms.txt, MCP, or agent-facing interactive console. Missing for 10: a single integrated interactive reference (e.g. rustdoc playground-style 'run' buttons on API docs), agent-facing tooling (llms.txt/MCP) to programmatically explore it, and independent confirmation the wasm examples are tied to the API reference itself.

   • [claimed-docs] “Learn how to use Bevy's types, traits and methods using the in-depth reference documentation, complete with inline examples.”
   • [claimed-docs] “Browse bevy examples compiled to wasm and running directly in your browser!”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): bevy.org serves no llms.txt (HTTP 404; docs.rs likewise) and no official MCP exists — communit…”
   • [probe] “PROBE llms.txt: HTTP 404 at https://bevy.org/llms.txt”

   proof ↗⚑ flag

   PlayCanvas—none0/10

   Evidence shows PlayCanvas has API docs (api.playcanvas.com/editor), llms.txt full docs, and starter templates, but no evidence of an interactive API reference page with embedded runnable code examples akin to a live sandbox integrated into the reference itself.

   ⚑ flag

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

   weight 2 · round drawn
   Bevy—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

   PlayCanvas—none0/10

   Explicit probe evidence shows no OpenAPI/Swagger spec exists at any expected path (all candidates 404); while llms.txt and an Editor API doc site exist, there is no machine-readable API spec download offered.

   • [probe] “PROBE openapi: all candidate paths 404 (https://developer.playcanvas.com/openapi.json, https://developer.playcanvas.com/swagger.json, https:…”

   proof ↗⚑ flag

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

   weight 1 · round to PlayCanvas
   Bevy—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

   PlayCanvas~partialclaimed3/10

   PlayCanvas documents Checkpoints for snapshotting/rolling back a project and an MCP server that acts on 'an open PlayCanvas Editor session,' which offers some safety net against irreversible changes, but there is no explicit sandbox/staging environment distinct from production data that an AI agent could test against. missing for 10: dedicated sandbox/staging project mode, explicit production-vs-test data separation, and evidence that MCP or automation actions can't touch the live production project.

   • [claimed-docs] “Checkpoints — Snapshot your project at any point and roll back if needed”
   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [claimed-docs] “With live editing, you can tweak materials, adjust positions, and even modify scripts while your application runs.”

   proof ↗⚑ flag

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

   weight 2 · round to Bevy
   Bevy!disputedcontradicted3/10

   Bevy publishes migration guides for each release (bevy-docs-15) implying some versioning discipline, but there is no documented deprecation policy, and hands-on evidence shows the API is pre-1.0 with frequent breaking changes each release requiring real rework (bevy-comm-12, bevy-comm-13, bevy-probe-rt-1), directly undercutting reliability for an AI agent trained on prior APIs. Missing for 10: an explicit deprecation/versioning policy document, semver guarantees, and evidence that breaking changes are flagged/deprecated before removal rather than silently changed.

   • [claimed-docs] “Every Bevy update brings new functionality and improvements. Follow these guides to migrate your project to the latest Bevy has to offer!”
   • [community] “Things have started to stabilize, but unless you're willing to get your hands dirty and deal with regular breaking changes, I don't yet reco…”
   • [community] “On the last update 0.10 -> 0.11, I had to make quite a few changes on my app, but this time it compiled out of the box!”
   • [probe] “PROBE runtime (recorded 2026-09-15): bevy resolves on crates.io — `cargo search bevy` → 'bevy = "0.19.1" # A refreshingly simple data-driven…”

   proof ↗⚑ flag

   PlayCanvas—none0/10

   No evidence pack item mentions API versioning semantics or a documented deprecation policy; the OpenAPI probe returned 404s and docs only describe scripting formats, editor features, and an MCP server, not stability guarantees for the API surface.

   • [probe] “PROBE openapi: all candidate paths 404 (https://developer.playcanvas.com/openapi.json, https://developer.playcanvas.com/swagger.json, https:…”

   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 PlayCanvas
   Bevy~partialprobed3/10

   Bevy has a first-party Bevy Remote Protocol that could support programmatic scene/entity manipulation, and a community tool (bevy_brp) built on it, but there is no official documentation, no llms.txt, and no official MCP server — the community tooling itself is described as nascent (70 stars). Since Bevy is a code-first Rust crate, most 'scripting' is done by writing/recompiling Rust code rather than through a documented runtime scriptable interface for driving an editor. Missing for 10: first-party documented API/schema for the Remote Protocol, official MCP or agent-facing tooling, evidence of hands-on agent use creating scenes/nodes and triggering builds via that interface.

   • [probe] “PROBE runtime negative (recorded 2026-09-15): bevy.org serves no llms.txt (HTTP 404; docs.rs likewise) and no official MCP exists — communit…”
   • [probe] “PROBE llms.txt: HTTP 404 at https://bevy.org/llms.txt”
   • [claimed-docs] “Create, save, and load ECS worlds using Bevy's Scene system”

   proof ↗⚑ flag

   PlayCanvas✓fullprobed8/10

   PlayCanvas ships an official, npm-published Editor MCP server that lets AI agents connect to an open Editor session, modify project data, and verify results, plus a separate documented scriptable Editor API (api.playcanvas.com/editor) for programmatic scene/node/property manipulation and automation. This directly satisfies the story of an agent driving the editor programmatically through a documented interface. Missing for 10: no independent/hands-on community report of an agent actually using the MCP server end-to-end, and no explicit documentation of triggering builds via this interface.

   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [claimed-docs] “This module is essential for developers looking to streamline their workflow, create custom editing tools, or integrate external data and sy…”
   • [probe] “official MCP server documented at https://developer.playcanvas.com/user-manual/editor/mcp-server/”
   • [probe] “PROBE runtime (recorded 2026-09-15): PlayCanvas ships the only OFFICIAL, open, npm-published editor MCP server of the eight engines — `npm v…”
   • [probe] “PROBE runtime (recorded 2026-09-15): developer.playcanvas.com serves llms.txt plus the largest llms-full.txt of the arena (2,053,637 bytes o…”

   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 to PlayCanvas
   Bevy!disputedcontradicted4/10

   Bevy has abundant examples and reference docs (bevy-docs-16, bevy-docs-22, bevy-docs-27) which help LLM familiarity, but concrete community evidence shows the API is unstable pre-1.0 with breaking changes almost every release, requiring real migration work each time (bevy-comm-12, bevy-comm-13, bevy-probe-rt-1) — meaning LLMs trained on older versions likely generate code that fails to compile against current APIs. Docs are also reported as thin/outdated relative to the pace of change (bevy-comm-14, bevy-comm-15), and there's no llms.txt or first-party AI-consumption docs (bevy-probe-1, bevy-probe-rt-2). missing for 10: evidence of first-try success rate for LLM-generated Bevy code, stable API surface across versions, and first-party AI-friendly documentation.

   • [community] “Things have started to stabilize, but unless you're willing to get your hands dirty and deal with regular breaking changes, I don't yet reco…”
   • [community] “On the last update 0.10 -> 0.11, I had to make quite a few changes on my app, but this time it compiled out of the box!”
   • [community] “I'm put off by the limited docs. I've read the Bevy book, only takes a few minutes, and just like that I'm out of resources to turn to when …”
   • [community] “There's an unofficial complement to the docs... Unfortunately it's somewhat out of date... The effort to keep it up to date is somewhat low …”
   • [probe] “PROBE runtime (recorded 2026-09-15): bevy resolves on crates.io — `cargo search bevy` → 'bevy = "0.19.1" # A refreshingly simple data-driven…”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): bevy.org serves no llms.txt (HTTP 404; docs.rs likewise) and no official MCP exists — communit…”
   • [claimed-docs] “Examples that show how to use the various features of Bevy.”

   proof ↗⚑ flag

   PlayCanvas~partialprobed6/10

   PlayCanvas offers strong LLM-friendly infrastructure — a dedicated llms.txt/llms-full.txt (over 2MB of docs), a stable, long-standing npm-published engine (2.22.2, 48k weekly downloads) with abundant public code examples and community history, plus scripting API docs — all of which support an LLM having 'seen' the API. However, community threads note real dev-experience quirks and unusual design choices that could trip up naive LLM-generated code, and there's no direct hands-on evidence of first-try LLM code generation success rates. Missing for 10: independent benchmark or testimonial confirming LLM-generated PlayCanvas code works correctly on first try, and no discussion of API stability/breaking-change history that would affect training-data staleness.

   • [probe] “PROBE runtime (recorded 2026-09-15): developer.playcanvas.com serves llms.txt plus the largest llms-full.txt of the arena (2,053,637 bytes o…”
   • [probe] “PROBE llms.txt: HTTP 200 at https://developer.playcanvas.com/llms.txt # PlayCanvas Developer Documentation > PlayCanvas is an open-source W…”
   • [github] “npm install playcanvas”
   • [community] “That issue was opened in 2022. Honestly if you really get into the nitty gritty of PC it becomes quickly apparent there's some very strange …”
   • [community] “I think Playcanvas would do well to focus on the basics, like being able to export/import variables in the standard js way, being able to de…”

   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 PlayCanvas
   Bevy—none0/10

   Bevy is a Rust game engine/library with no evidence of an official in-engine AI assistant; probes confirm no llms.txt, no official MCP, and only nascent third-party tooling (bevy_brp).

   • [probe] “PROBE llms.txt: HTTP 404 at https://bevy.org/llms.txt”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): bevy.org serves no llms.txt (HTTP 404; docs.rs likewise) and no official MCP exists — communit…”

   proof ↗⚑ flag

   PlayCanvas~partialprobed6/10

   PlayCanvas ships an official, npm-published Editor MCP Server that lets external AI assistants connect to a live Editor session to modify project data, script entities, and verify changes via the viewport—directly enabling AI-assisted script generation and scene/asset scaffolding (playcanvas-docs-6, playcanvas-probe-rt-1). However, this is an MCP bridge for third-party assistants rather than a built-in chat/assistant panel inside the engine UI, and there's no dedicated in-engine API Q&A assistant beyond the llms.txt docs feed. Missing for 10: a native in-editor chat/assistant UI, and explicit evidence of it answering free-form API questions rather than just executing structured edits.

   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [probe] “official MCP server documented at https://developer.playcanvas.com/user-manual/editor/mcp-server/”
   • [probe] “PROBE runtime (recorded 2026-09-15): PlayCanvas ships the only OFFICIAL, open, npm-published editor MCP server of the eight engines — `npm v…”
   • [probe] “PROBE runtime (recorded 2026-09-15): developer.playcanvas.com serves llms.txt plus the largest llms-full.txt of the arena (2,053,637 bytes o…”

   proof ↗⚑ flag

Formats

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

   weight 2 · round drawn
   Bevy—none0/10

   No evidence anywhere in the pack mentions glTF, FBX, USD, or any interchange-format import/asset-pipeline support; only glTF is a commonly known Bevy asset format but it's not cited here. Missing for 10: any docs or community mention of glTF/FBX/USD import, format fidelity, or asset-pipeline tooling.

   ⚑ flag

   PlayCanvas—none0/10

   The evidence pack contains no mention of glTF, FBX, or USD import support, nor any asset-pipeline/import documentation; it covers editor, scripting, MCP server, and community sentiment unrelated to file format import.

   ⚑ 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 drawn
   Bevy~partialcommunity3/10

   Bevy's Asset V2 system does support preprocessing and .meta files, which one community commenter calls 'super useful' for pipeline automation, but no first-party docs describe import hooks, presets, or scripting workflows for batch/automated asset processing. missing for 10: official documentation on asset import hooks/presets, evidence of scripted/batch pipeline tooling, and independent confirmation beyond a single community mention.

   • [community] “Bevy is one of my favorite game engines, especially for larger projects. Asset V2 preprocessing and .meta files look super useful.”

   proof ↗⚑ flag

   PlayCanvas~partialcommunity3/10

   The Editor API is explicitly billed for scripting custom tools and integrating external systems (playcanvas-docs-9), and the community references playcanvas-sync for mapping project assets to a local filesystem (playcanvas-comm-10) and the MCP server for programmatic project data changes (playcanvas-docs-6), all of which imply some automation capability. However, there is no documented import-hook system, asset presets, or a dedicated pipeline-scripting API specifically for processing incoming assets automatically. Missing for 10: explicit asset import hooks, configurable import presets, documented pipeline scripts triggered on asset ingestion, and independent confirmation these tools eliminate manual per-asset clicking.

   • [claimed-docs] “This module is essential for developers looking to streamline their workflow, create custom editing tools, or integrate external data and sy…”
   • [community] “I recommend checking out the newly released playcanvas-sync tools which let you map your PlayCanvas project's assets to your local machine's…”
   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”

   proof ↗⚑ flag

Marketplace

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

   weight 2 · round to Bevy
   Bevy~partialcommunity5/10

   Bevy explicitly maintains an official third-party 'Assets' page listing community plugins, tools, and learning resources (bevy-docs-17), and community comments confirm an active ecosystem contributing new features and crates (bevy-comm-19). However, this is a curated links page rather than an integrated in-engine asset store, and the ecosystem is described as young/fragmented with docs gaps and frequent breaking changes affecting third-party plugin compatibility (bevy-comm-12, bevy-comm-15). Missing for 10: evidence of a large volume/maturity of ready-made models or marketplace-scale assets, integrated store UI, and quantified ecosystem size or quality assurance for third-party plugins.

   • [claimed-docs] “A collection of third-party Bevy assets, plugins, learning resources, and apps made by the community.”
   • [community] “Something delightful about this update: it has a lot of new features, some very early, but all by different authors. Seems like such a commu…”
   • [community] “Things have started to stabilize, but unless you're willing to get your hands dirty and deal with regular breaking changes, I don't yet reco…”
   • [community] “There's an unofficial complement to the docs... Unfortunately it's somewhat out of date... The effort to keep it up to date is somewhat low …”

   proof ↗⚑ flag

   PlayCanvas—none0/10

   The evidence pack shows PlayCanvas has an editor, engine, scripting system, MCP server, and npm-published engine, but nowhere mentions an asset store, marketplace, or plugin/package ecosystem for ready-made models or tools. No community or docs citation references anything resembling a store of third-party assets or plugins.

   ⚑ flag

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

   weight 2 · round to PlayCanvas
   Bevy—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

   PlayCanvas~partialprobed4/10

   PlayCanvas exposes a scriptable Editor API (api.playcanvas.com/editor) explicitly for building custom editing tools and integrating external data, and an official MCP server that lets AI assistants modify project data programmatically — both imply automation potential across many assets, but neither doc explicitly describes bulk/batch operations (e.g., multi-entity edits, batch asset import) or gives a hands-on example of many-item automation. Missing for 10: explicit bulk-edit/batch API examples, documented multi-item scripting workflows, and independent confirmation of large-scale automation via the MCP server or Editor API.

   • [claimed-docs] “This module is essential for developers looking to streamline their workflow, create custom editing tools, or integrate external data and sy…”
   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [probe] “PROBE runtime (recorded 2026-09-15): PlayCanvas ships the only OFFICIAL, open, npm-published editor MCP server of the eight engines — `npm v…”

   proof ↗⚑ flag

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

   weight 3 · round drawn
   Bevy—none0/10

   The evidence pack describes Bevy's ECS, rendering, audio, and UI features but never mentions an event/trigger/rule system (e.g., Bevy Events, Observers, or ECS hooks) that would let a user define rules firing automatically on events. While such automation is plausible for a game engine's ECS, no evidence in the pack substantiates it.

   ⚑ flag

   PlayCanvas—none0/10

   The evidence pack covers scripting syntax, editor collaboration, physics components, and the MCP server for AI-assisted project editing, but contains no documentation of an explicit event/rule system where users can define triggers that automatically fire actions (e.g., event listeners, condition-action bindings) for automation purposes. Missing for 10: documentation of an event-trigger/rule engine, examples of defining conditional automation, and evidence tying this to AI-native workflows.

   ⚑ flag

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

   weight 1 · round to PlayCanvas
   Bevy—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

   PlayCanvas~partialcommunity5/10

   PlayCanvas Editor has a Checkpoints feature to snapshot a project and roll back, which covers basic versioning/rollback of editor state (including changes made via the MCP-driven AI automation), but there's no documented diff/review workflow for automations and community feedback explicitly flags the lack of standard source-control integration as a pain point. missing for 10: dedicated review/diff tooling for automation changes, git-style commit history, and any evidence that checkpoints integrate specifically with AI-driven MCP edits.

   • [claimed-docs] “Checkpoints — Snapshot your project at any point and roll back if needed”
   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [community] “I think Playcanvas would do well to focus on the basics, like being able to export/import variables in the standard js way, being able to de…”

   proof ↗⚑ flag

2d

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

   weight 2 · round to Bevy
   Bevy~partialclaimed5/10

   Bevy's official docs explicitly list 2D rendering as a first-class feature alongside 3D (bevy-docs-2, bevy-docs-3), suggesting parity rather than a 3D-only focus, and community feedback confirms active engine use for real projects. However, there is no evidence in the pack of built-in tilemap support or first-party 2D physics (these are known to be third-party crates in the Bevy ecosystem), so the story's specific claims about tilemaps and 2D physics being first-class are unconfirmed. Missing for 10: evidence of native/first-party tilemap support, evidence of native/first-party 2D physics integration, and any community confirmation of 2D-specific workflow maturity.

   • [claimed-docs] “Render real-time 2D graphics for games and apps”
   • [claimed-docs] “A modern and flexible 3D renderer”
   • [claimed-docs] “Extensible: custom shaders, materials, and render pipelines”

   proof ↗⚑ flag

   PlayCanvas—none0/10

   Evidence pack covers 3D features (rigidbody/collision physics, Gaussian Splatting, Engine, Editor) but contains no mention of sprites, tilemaps, or a 2D physics system — PlayCanvas is documented here purely as a 3D-first engine. This is a fair question for a game engine, but no evidence supports a first-class 2D workflow, so it's 'none' rather than 'na'.

   • [claimed-docs] “The rigidbody component decides how an entity moves, the collision component gives it a physical shape, and the alpha joint component constr…”
   • [github] “Gaussian Splatting - First-class support for loading and rendering 3D Gaussian Splats”

   proof ↗⚑ flag

Performance

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

   weight 2 · round to Bevy
   Bevy~partialcommunity4/10

   Bevy's data-oriented ECS is well documented as the foundation for all engine/game logic (bevy-docs-1, bevy-docs-14, bevy-docs-20), and community accounts corroborate its data-driven, ECS-first workflow (bevy-comm-17). However, the evidence pack contains no mention of a built-in profiler/diagnostics tool, explicit job/parallel-system scheduling, or GPU instancing for heavy scenes — core parts of the story. Missing for 10: dedicated profiler tooling (e.g. tracing/diagnostics plugin), explicit job-system/parallelism documentation, and instancing support evidence.

   • [claimed-docs] “All engine and game logic uses Bevy ECS, a custom Entity Component System”
   • [claimed-docs] “Components: Rust structs that implement the Component trait”
   • [claimed-docs] “Unlike other Rust ECS implementations, which often require complex lifetimes, traits, builder patterns, or macros, Bevy ECS uses normal Rust…”
   • [community] “Pros: Very nice to work in Rust engine + Rust game. Once you get your brain thinking ECS it's tough to go back, feels very flexible. Very li…”

   proof ↗⚑ flag

   PlayCanvas—none0/10

   The evidence pack contains no mention of a profiler, ECS architecture, job/worker system, or GPU instancing for scaling heavy scenes — only physics components, Gaussian splatting, and editor/collab features are documented. This is a fair axis for any game engine, but PlayCanvas's pack simply doesn't address it.

   ⚑ flag

Physics

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

   weight 2 · round to PlayCanvas
   Bevy—none0/10

   The evidence pack covers ECS, rendering, audio, UI, and scenes but contains no mention of physics, rigid bodies, collision detection, or raycasting capabilities. Built-in physics is a fair question for a game engine's core-engine axis, but nothing in the docs or community evidence shows Bevy ships this out of the box.

   ⚑ flag

   PlayCanvas~partialcommunity6/10

   Docs confirm built-in rigidbody, collision, and joint components enabling physics simulation out of the box (playcanvas-docs-8), and community sources corroborate PlayCanvas as a capable, well-designed engine used in shipped games. However, raycasts are not explicitly mentioned, and there's no hands-on evidence or tutorial demonstrating physics working smoothly without setup friction (e.g., Ammo.js/physics engine integration steps). Missing for 10: explicit raycast documentation, independent hands-on confirmation of zero-config physics setup, and detail on which physics backend is bundled vs. requires separate install.

   • [claimed-docs] “The rigidbody component decides how an entity moves, the collision component gives it a physical shape, and the alpha joint component constr…”
   • [community] “THREE.js is very low-level framework, while PlayCanvas additionally to low-level engine access has game framework, which will allow you to c…”
   • [community] “I haven't used it, but I remember looking at the minified code a while back when it was first released. It looks very well done, by someone …”

   proof ↗⚑ 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 Bevy
   Bevy~partialcommunity5/10

   Docs confirm a 'modern and flexible 3D renderer' with extensible custom shaders/materials/pipelines, and community hands-on feedback confirms shadows exist (though called 'jagged/low-res, reminds me of early Unity shadows'). However, the evidence pack never mentions global illumination, baked lighting, or a post-processing stack explicitly. Missing for 10: explicit documentation of GI/baked lighting support, explicit post-processing feature list, and independent corroboration of PBR material quality beyond the shadow-quality caveat.

   • [claimed-docs] “A modern and flexible 3D renderer”
   • [claimed-docs] “Extensible: custom shaders, materials, and render pipelines”
   • [community] “Not a criticism, but model projected shadows are very jagged or really low-res, reminds me of early Unity shadows.”

   proof ↗⚑ flag

   PlayCanvas—none0/10

   The evidence pack documents scripting, editor collaboration, physics, MCP integration, and Gaussian splatting support, but contains no first-party or community evidence about PBR materials, global illumination/baked lighting, shadow systems, or a post-processing pipeline. Per the rules, absence of evidence for this applicable rendering-feature axis must be scored as 'none' rather than inferred from outside knowledge.

   ⚑ 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 PlayCanvas
   Bevy—none0/10

   Evidence mentions a Scene system for saving/loading ECS worlds (bevy-docs-8) but nothing about its text format being diffable/mergeable, nor any built-in multi-user collaboration tooling. The 'code-first' workflow noted in bevy-probe-rt-2 is framed around agent-driven development, not team version-control workflows, so it doesn't substantiate this story.

   • [claimed-docs] “Create, save, and load ECS worlds using Bevy's Scene system”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): bevy.org serves no llms.txt (HTTP 404; docs.rs likewise) and no official MCP exists — communit…”

   proof ↗⚑ flag

   PlayCanvas!disputedcontradicted4/10

   PlayCanvas markets real-time multi-user editing as solving merge conflicts entirely (docs-4, docs-13) rather than a diffable/VCS-friendly text format, but hands-on community reports concretely contradict the 'plays well with version control' framing: developers note the project lives on PlayCanvas's servers with 'no easy local dev environment' and that basics like 'using your own source control' are missing, with unofficial third-party tools (playcanvas-sync) needed just to sync assets locally, and uploading being a 'deal breaker' for offline/local workflows. Checkpoints (docs-5) offer some rollback safety but are not the same as git-based diff/merge tooling. missing for 10: official git-friendly/text-diffable scene format, first-party local-file sync equivalent to real VCS integration, and evidence the community-reported local-dev gap has been resolved.

   • [claimed-docs] “Multiple developers, artists, and designers can build the same scene simultaneously—no merge conflicts, no stepping on each other's toes.”
   • [claimed-docs] “With live editing, you can tweak materials, adjust positions, and even modify scripts while your application runs.”
   • [claimed-docs] “Checkpoints — Snapshot your project at any point and roll back if needed”
   • [community] “I think Playcanvas would do well to focus on the basics, like being able to export/import variables in the standard js way, being able to de…”
   • [community] “When I was working at a mobile game studio, we looked at this as an engine for a project. At the time we decided not to go with it since all…”
   • [community] “I think the engine is open source; but the real appeal is using the real time collab online tool, which is proprietary and had the drawbacks…”
   • [community] “I'd love to be able to use their scene editor offline, uploading assets is a deal breaker.”
   • [community] “I recommend checking out the newly released playcanvas-sync tools which let you map your PlayCanvas project's assets to your local machine's…”

   proof ↗⚑ flag

Editor

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

   weight 3 · round to PlayCanvas
   Bevy—none0/10

   Bevy's evidence describes a code-first Rust ECS engine (components, systems, scenes-as-data, hot reloading) but nothing about a visual editor with viewport, inspector, or prefab/scene composition UI; comment bevy-comm-8 even suggests users hope NOT to be forced into an in-engine editor, and probes show no official tooling filling this gap. Missing for full/partial credit: any first-party viewport/inspector GUI, prefab authoring workflow, or scene-composition editor.

   • [claimed-docs] “Create, save, and load ECS worlds using Bevy's Scene system”
   • [claimed-docs] “Get instant feedback on your changes without app restarts or recompiles”
   • [community] “The integrated code editor in Godot is actually something I don't like... I hope that Bevy users won't be forced to use the Bevy editor for …”

   proof ↗⚑ flag

   PlayCanvas~partialcommunity6/10

   Docs confirm a full drag-and-drop visual Editor with real-time collaborative scene building, live editing of materials/positions, and checkpoint/versioning (playcanvas-docs-3, docs-4, docs-5, docs-13), which matches the viewport+scene-composition part of the story. However, no evidence explicitly documents an 'inspector' panel or a 'prefab' system by name, and community reports flag real dev-experience friction (no easy local dev, assets must be uploaded, offline editing not supported) that complicate treating the editor as the primary, frictionless build workflow. missing for 10: explicit inspector/prefab terminology and documentation, independent hands-on confirmation of prefab workflow, resolution of community-reported offline/local-dev friction.

   • [claimed-docs] “Want drag-and-drop scene building, real-time collaboration, or prefer visual tools over code”
   • [claimed-docs] “Multiple developers, artists, and designers can build the same scene simultaneously—no merge conflicts, no stepping on each other's toes.”
   • [claimed-docs] “Checkpoints — Snapshot your project at any point and roll back if needed”
   • [claimed-docs] “With live editing, you can tweak materials, adjust positions, and even modify scripts while your application runs.”
   • [community] “When I was working at a mobile game studio, we looked at this as an engine for a project. At the time we decided not to go with it since all…”
   • [community] “I'd love to be able to use their scene editor offline, uploading assets is a deal breaker.”

   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 PlayCanvas
   Bevy—none0/10

   Bevy's evidence shows only a code-first workflow (ECS, scenes, plugins) and mentions no official editor application to extend; the closest hint is a third-party 'bevy_brp' remote-protocol tool with just 70 stars, not first-party editor scripting/plugin support for manipulating scenes and assets. missing for 10: any first-party editor product, documented editor scripting/plugin API, or mature ecosystem tooling for automating scene/asset manipulation via an editor UI.

   • [probe] “PROBE runtime negative (recorded 2026-09-15): bevy.org serves no llms.txt (HTTP 404; docs.rs likewise) and no official MCP exists — communit…”
   • [claimed-docs] “Create, save, and load ECS worlds using Bevy's Scene system”

   proof ↗⚑ flag

   PlayCanvas✓fullprobed7/10

   PlayCanvas explicitly documents a scriptable Editor API module (api.playcanvas.com/editor) built 'for developers looking to... create custom editing tools, or integrate external data and systems into the PlayCanvas Editor environment,' plus an official MCP server for AI-driven automation of live Editor sessions, and community-built sync tools for local file mapping — together showing programmatic extension of the editor itself. Missing for 10: concrete example plugins/marketplace or hands-on demonstration of a third-party editor tool built with this API, and no independent review confirming ease of use for this specific API (only general dev-experience complaints exist).

   • [claimed-docs] “This module is essential for developers looking to streamline their workflow, create custom editing tools, or integrate external data and sy…”
   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [probe] “PROBE runtime (recorded 2026-09-15): PlayCanvas ships the only OFFICIAL, open, npm-published editor MCP server of the eight engines — `npm v…”
   • [community] “I recommend checking out the newly released playcanvas-sync tools which let you map your PlayCanvas project's assets to your local machine's…”

   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 to Bevy
   Bevy~partialprobed5/10

   Bevy is a code-first Rust library built and run via cargo, with no mandatory editor (bevy-docs-21, bevy-comm-8, bevy-probe-rt-2), which inherently supports command-line/CI builds. However, there is no explicit documentation of a headless mode flag, export pipeline, or CI-specific tooling/examples, and no official CI templates or GitHub Actions references are present in the evidence pack. missing for 10: explicit headless-mode/export documentation, CI pipeline examples or templates, and confirmation of asset-building/export automation without a GUI step.

   • [claimed-docs] “Bevy is just a normal Rust dependency. You can either add it to an existing Rust project or create a new one.”
   • [community] “The integrated code editor in Godot is actually something I don't like... I hope that Bevy users won't be forced to use the Bevy editor for …”
   • [probe] “PROBE runtime negative (recorded 2026-09-15): bevy.org serves no llms.txt (HTTP 404; docs.rs likewise) and no official MCP exists — communit…”
   • [probe] “PROBE runtime (recorded 2026-09-15): bevy resolves on crates.io — `cargo search bevy` → 'bevy = "0.19.1" # A refreshingly simple data-driven…”

   proof ↗⚑ flag

   PlayCanvas~partialcommunity4/10

   The standalone Engine is a plain npm package usable with Vite/TypeScript scaffolding, so Engine-only projects can plausibly be built and bundled headlessly via a standard `vite build` in CI (playcanvas-gh-2, playcanvas-docs-1, playcanvas-docs-7). However, PlayCanvas's primary workflow is the cloud Editor, and community reports confirm no easy local dev environment or native CLI export — code/assets live on PlayCanvas's servers, requiring third-party 'playcanvas-sync' tooling and manual tinkering to approximate a local/CI workflow (playcanvas-comm-8, playcanvas-comm-9, playcanvas-comm-10). No first-party CLI/CI build-and-export tool for Editor projects is documented anywhere in the evidence. Missing for 10: an official CLI/CI export command for Editor-based projects, documentation of headless Editor project builds, and independent confirmation that Editor-based CI pipelines work reliably.

   • [github] “npm install playcanvas”
   • [claimed-docs] “Use `create-playcanvas` to scaffold a Vite and TypeScript project for the Engine, React, or Web Components from one of 12 runnable starters.”
   • [claimed-docs] “Build applications against the Engine directly. Learn how to use the Engine standalone.”
   • [community] “When I was working at a mobile game studio, we looked at this as an engine for a project. At the time we decided not to go with it since all…”
   • [community] “It's certainly not super obvious to setup but there are ways to use PlayCanvas with local setup... with some tinkering you can have hot modu…”
   • [community] “I recommend checking out the newly released playcanvas-sync tools which let you map your PlayCanvas project's assets to your local machine's…”

   proof ↗⚑ flag

Server

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

   weight 2 · round drawn
   Bevy—none0/10

   The evidence pack covers Bevy's ECS, rendering, UI, audio, and platform support, but contains no mention of a headless/dedicated-server build mode, disabling rendering plugins, or server-runtime configuration. Since this is a plausible and common need for a game engine, absence of evidence means the axis is unmet rather than inapplicable.

   ⚑ flag

   PlayCanvas—none0/10

   The evidence pack shows PlayCanvas as a browser-focused WebGL/WebGPU engine with npm packages, Editor, and MCP server tooling, but nothing about a dedicated headless/server-runtime build without rendering for running game logic on servers. Missing for 10: any docs or GitHub evidence of a headless Node.js server build, server-side simulation mode, or rendering-free runtime.

   • [claimed-docs] “Build applications against the Engine directly. Learn how to use the Engine standalone.”
   • [github] “npm install playcanvas”
   • [probe] “PROBE runtime (recorded 2026-09-15): developer.playcanvas.com serves llms.txt plus the largest llms-full.txt of the arena (2,053,637 bytes o…”

   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 drawn
   Bevy—none0/10

   The evidence pack contains no mention of headless mode, CI test execution, integration testing, or automated test frameworks for Bevy game logic — nothing about running engine/game tests without a display or in continuous integration.

   ⚑ flag

   PlayCanvas—none0/10

   No evidence of a testing framework, headless mode, or CI integration for running unit/integration tests against the PlayCanvas engine; docs cover scripting, editor, MCP server, and standalone engine usage but never mention headless test execution or CI workflows.

   ⚑ 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
   Bevy—none0/10

   Evidence documents Bevy's open-source MIT/Apache-2.0 licensing and community activity, but nothing about a governing foundation, published finances, or an official public roadmap a studio could plan against — only migration guides for past releases are mentioned. missing for 10: evidence of a foundation or legal entity, published budget/financials, and a forward-looking public roadmap.

   • [claimed-docs] “It is free and open-source forever under your choice of the MIT or Apache 2.0 licenses.”
   • [claimed-docs] “100% free. Forever and always * Open Source under the permissive MIT or Apache 2.0 licenses * No contracts * No license fees * No sa…”
   • [claimed-docs] “Every Bevy update brings new functionality and improvements. Follow these guides to migrate your project to the latest Bevy has to offer!”
   • [community] “Something delightful about this update: it has a lot of new features, some very early, but all by different authors. Seems like such a commu…”

   proof ↗⚑ flag

   PlayCanvas—none0/10

   No evidence of a governing foundation, published financials, or a public roadmap; PlayCanvas is run as a commercial product (subscription plans mentioned) with no transparency artifacts cited. Community comments discuss engine features and dev-experience, not governance or funding.

   ⚑ 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 Bevy
   Bevy✓fullprobed9/10

   Bevy's own site explicitly states it is 100% free forever, MIT OR Apache-2.0 licensed, with no contracts, no license fees, and no sales cuts, directly satisfying the studio-lead's ask of no royalties or per-install fees. This is corroborated independently by crates.io license metadata and by community commentary praising the permissive MIT licensing as 'no strings attached.' Missing for 10: no explicit legal/contract analysis or enterprise-scale case study confirming zero royalty obligations at large studio scale.

   • [claimed-docs] “100% free. Forever and always * Open Source under the permissive MIT or Apache 2.0 licenses * No contracts * No license fees * No sa…”
   • [claimed-docs] “It is free and open-source forever under your choice of the MIT or Apache 2.0 licenses.”
   • [community] “MIT License, well done! It's so refreshing to see things released with no strings attached... a breathe of fresh air as a potential end user…”
   • [probe] “PROBE runtime (recorded 2026-09-15): bevy resolves on crates.io — `cargo search bevy` → 'bevy = "0.19.1" # A refreshingly simple data-driven…”

   proof ↗⚑ flag

   PlayCanvas✓fullprobed7/10

   The core PlayCanvas Engine is confirmed MIT-licensed and open source ('MIT engine runtime' in playcanvas-probe-rt-2; community confirms 'the engine is open source' in playcanvas-comm-11 and playcanvas-comm-16), meaning a studio can ship and monetize games without royalties or per-install fees on the runtime itself. However, evidence also shows the hosted Editor/collaboration tooling is a paid subscription (e.g., $15/month for private projects, playcanvas-comm-4), which is a studio-tooling cost rather than a revenue royalty, so it doesn't contradict the engine's permissive licensing but adds nuance. Missing for 10: explicit vendor documentation stating 'no royalties/no revenue share' policy and independent legal/community confirmation of unrestricted commercial use terms.

   • [probe] “PROBE runtime (recorded 2026-09-15): developer.playcanvas.com serves llms.txt plus the largest llms-full.txt of the arena (2,053,637 bytes o…”
   • [community] “I think the engine is open source; but the real appeal is using the real time collab online tool, which is proprietary and had the drawbacks…”
   • [community] “It's an open source javascript game engine that is kinda like halfway between something like three.js and e.g. Unity—pretty lightweight, but…”
   • [community] “Every time I've taken a look at this engine it has always felt very limited. And with a $15/month subscription just to be able to create pri…”

   proof ↗⚑ flag

Source

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

   weight 2 · round to Bevy
   Bevy✓fullprobed9/10

   Bevy is fully open-source (MIT/Apache 2.0), with source hosted openly, allowing developers to read and modify the engine itself; community confirms code is clean/readable and license is unrestricted ('no strings attached'). Missing for 10: no explicit hands-on account of a developer patching/forking the engine source to unblock themselves, only license and code-quality corroboration.

   • [claimed-docs] “It is free and open-source forever under your choice of the MIT or Apache 2.0 licenses.”
   • [claimed-docs] “100% free. Forever and always * Open Source under the permissive MIT or Apache 2.0 licenses * No contracts * No license fees * No sa…”
   • [claimed-docs] “Why are we continuing to build up the ecosystems of closed-source monopolies that take cuts of our sales and deny us visibility into the tec…”
   • [community] “Got the chance of running the examples and glance over the code... it looks incredibly elegant and clean. Almost feels like this could make …”
   • [community] “MIT License, well done! It's so refreshing to see things released with no strings attached... a breathe of fresh air as a potential end user…”
   • [probe] “PROBE runtime (recorded 2026-09-15): bevy resolves on crates.io — `cargo search bevy` → 'bevy = "0.19.1" # A refreshingly simple data-driven…”

   proof ↗⚑ flag

   PlayCanvas✓fullprobed8/10

   The PlayCanvas Engine is confirmed open source (MIT) and published on GitHub/npm, allowing developers to read and modify the core engine code directly, corroborated by community comment that 'the engine is open source' and runtime probes confirming the MIT license and public repo. Missing for 10: explicit contribution/build docs or a first-party statement of the license terms, and no independent hands-on account of someone actually patching engine internals.

   • [github] “Gaussian Splatting - First-class support for loading and rendering 3D Gaussian Splats”
   • [github] “npm install playcanvas”
   • [community] “I think the engine is open source; but the real appeal is using the real time collab online tool, which is proprietary and had the drawbacks…”
   • [probe] “PROBE runtime (recorded 2026-09-15): developer.playcanvas.com serves llms.txt plus the largest llms-full.txt of the arena (2,053,637 bytes o…”

   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 to Bevy
   Bevy✓fullcommunity7/10

   Bevy is licensed under MIT/Apache 2.0 with explicit 'no contracts, no license fees, no sales cuts, forever' commitments, and these are irrevocable open-source licenses that cannot retroactively reprice already-shipped games — corroborated by community praise for the license having 'no strings attached.' Missing for 10: a long multi-year track record (Bevy is a young, pre-1.0 project) and any explicit governance statement committing to never relicense future versions restrictively.

   • [claimed-docs] “100% free. Forever and always * Open Source under the permissive MIT or Apache 2.0 licenses * No contracts * No license fees * No sa…”
   • [claimed-docs] “It is free and open-source forever under your choice of the MIT or Apache 2.0 licenses.”
   • [community] “MIT License, well done! It's so refreshing to see things released with no strings attached... a breathe of fresh air as a potential end user…”

   proof ↗⚑ flag

   PlayCanvas—none0/10

   No evidence in the pack addresses pricing/licensing history, terms stability, or retroactive repricing of shipped games; only a $15/month subscription mention and a link to the plans page appear, with no discussion of contract stability or track record.

   ⚑ flag

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

   weight 2 · round to PlayCanvas
   Bevy—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

   PlayCanvas~partialprobed6/10

   PlayCanvas exposes a scriptable Editor API (api.playcanvas.com/editor) for custom editing tools and integrations, plus an official MCP server that lets AI assistants modify project data and verify results via the viewport — going beyond a typical 'no API' game engine. However there is no discoverable REST/OpenAPI spec (404s across probed endpoints), and no documentation explicitly claims full UI-API parity; some Editor-only features (drag-and-drop scene building, real-time collaboration) are framed as UI-first conveniences without confirmed programmatic equivalents. missing for 10: an explicit parity statement/spec covering all UI actions, a formal REST/OpenAPI contract, and independent confirmation that collaborative/visual editor features are fully scriptable.

   • [claimed-docs] “The PlayCanvas Editor MCP Server connects AI assistants to an open PlayCanvas Editor session. It can modify project data and verify the resu…”
   • [claimed-docs] “This module is essential for developers looking to streamline their workflow, create custom editing tools, or integrate external data and sy…”
   • [probe] “official MCP server documented at https://developer.playcanvas.com/user-manual/editor/mcp-server/”
   • [probe] “PROBE runtime (recorded 2026-09-15): PlayCanvas ships the only OFFICIAL, open, npm-published editor MCP server of the eight engines — `npm v…”
   • [probe] “PROBE openapi: all candidate paths 404 (https://developer.playcanvas.com/openapi.json, https://developer.playcanvas.com/swagger.json, https:…”
   • [claimed-docs] “Want drag-and-drop scene building, real-time collaboration, or prefer visual tools over code”

   proof ↗⚑ flag

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

   weight 3 · round drawn
   Bevy~partialprobed5/10

   Bevy is a local, open-source Rust engine (MIT/Apache-2.0) with no cloud data lock-in, and its Scene system lets you save/load ECS worlds in the open RON format, which aligns with the openness theme. However there's no explicit documentation or tooling framed around 'exporting all your data and leaving' (e.g., data migration guides, guaranteed format stability) since Bevy isn't a hosted service holding user data in the first place. Missing for 10: explicit data-export/migration documentation, guarantees around long-term format stability given breaking API changes each release, and any first-party statement on data portability beyond the general OSS license.

   • [claimed-docs] “Create, save, and load ECS worlds using Bevy's Scene system”
   • [claimed-docs] “It is free and open-source forever under your choice of the MIT or Apache 2.0 licenses.”
   • [claimed-docs] “100% free. Forever and always * Open Source under the permissive MIT or Apache 2.0 licenses * No contracts * No license fees * No sa…”
   • [probe] “PROBE runtime (recorded 2026-09-15): bevy resolves on crates.io — `cargo search bevy` → 'bevy = "0.19.1" # A refreshingly simple data-driven…”

   proof ↗⚑ flag

   PlayCanvas~partialcommunity5/10

   The engine itself is open-source (MIT, npm-published) and PlayCanvas offers 'Download Apps for Self-hosting', plus community tooling (playcanvas-sync) to map project assets to a local filesystem, giving users a path to exit the platform with their code/engine. However, there is no first-party documentation of a comprehensive 'export all project data in open formats' feature, and community reports explicitly flag that code/collaboration data lives on PlayCanvas's servers with no easy local dev environment, undercutting a full data-portability story. Missing for 10: an official bulk data-export tool/format for scenes, assets and editor project state, and independent confirmation that exported data is fully open and complete.

   • [claimed-docs] “Download Apps for Self-hosting”
   • [community] “When I was working at a mobile game studio, we looked at this as an engine for a project. At the time we decided not to go with it since all…”
   • [community] “It's certainly not super obvious to setup but there are ways to use PlayCanvas with local setup... with some tinkering you can have hot modu…”
   • [community] “I recommend checking out the newly released playcanvas-sync tools which let you map your PlayCanvas project's assets to your local machine's…”
   • [community] “I think the engine is open source; but the real appeal is using the real time collab online tool, which is proprietary and had the drawbacks…”
   • [github] “npm install playcanvas”

   proof ↗⚑ flag

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

   weight 2 · round drawn
   Bevy✓fullprobed9/10

   Bevy's source and docs are explicitly MIT OR Apache-2.0 licensed, confirmed both by first-party docs and independent runtime crates.io metadata, and community commenters corroborate the open, permissive licensing and code readability. Missing for 10: no direct GitHub repo citation in the evidence pack, though license and source availability are otherwise well-documented.

   • [claimed-docs] “It is free and open-source forever under your choice of the MIT or Apache 2.0 licenses.”
   • [claimed-docs] “100% free. Forever and always * Open Source under the permissive MIT or Apache 2.0 licenses * No contracts * No license fees * No sa…”
   • [community] “MIT License, well done! It's so refreshing to see things released with no strings attached... a breathe of fresh air as a potential end user…”
   • [probe] “PROBE runtime (recorded 2026-09-15): bevy resolves on crates.io — `cargo search bevy` → 'bevy = "0.19.1" # A refreshingly simple data-driven…”

   proof ↗⚑ flag

   PlayCanvas✓fullprobed9/10

   PlayCanvas Engine is confirmed open source (GitHub repo, MIT license, npm-published), and community commentary independently corroborates 'the engine is open source' (playcanvas-comm-11, comm-16). The full engine source is browsable on GitHub and versioned, satisfying an AI-native user's ability to read source under an open license; missing for 10: explicit license file text/OSI confirmation cited directly in evidence.

   • [github] “Gaussian Splatting - First-class support for loading and rendering 3D Gaussian Splats”
   • [github] “npm install playcanvas”
   • [community] “I think the engine is open source; but the real appeal is using the real time collab online tool, which is proprietary and had the drawbacks…”
   • [community] “It's an open source javascript game engine that is kinda like halfway between something like three.js and e.g. Unity—pretty lightweight, but…”
   • [probe] “PROBE runtime (recorded 2026-09-15): developer.playcanvas.com serves llms.txt plus the largest llms-full.txt of the arena (2,053,637 bytes o…”

   proof ↗⚑ flag

4. ai-native userSelf-host the core product

   weight 3 · round to Bevy
   Bevy✓fullcommunity7/10

   Bevy is not a hosted service at all — it's an open-source (MIT/Apache-2.0) Rust library added directly as a dependency to your own project and compiled/run entirely on your own machine, satisfying self-hosting by default with no server or cloud dependency (bevy-docs-18, bevy-docs-21, bevy-docs-25). Community corroboration confirms the open license and local dev workflow (bevy-comm-2). missing for 10: explicit vendor-authored self-hosting/deployment guidance (e.g., docs discussing running Bevy apps as self-hosted servers or headless builds) and independent verification of self-hosted production deployments.

   • [claimed-docs] “It is free and open-source forever under your choice of the MIT or Apache 2.0 licenses.”
   • [claimed-docs] “Bevy is just a normal Rust dependency. You can either add it to an existing Rust project or create a new one.”
   • [claimed-docs] “100% free. Forever and always * Open Source under the permissive MIT or Apache 2.0 licenses * No contracts * No license fees * No sa…”
   • [community] “MIT License, well done! It's so refreshing to see things released with no strings attached... a breathe of fresh air as a potential end user…”

   proof ↗⚑ flag

   PlayCanvas!disputedcontradicted5/10

   The core Engine is open-source (MIT, npm-published) and documented for standalone/self-hosted use (playcanvas-docs-7, playcanvas-gh-2), but the actual PlayCanvas product most users mean—the Editor/collaboration platform—is proprietary SaaS with no self-hosting option; community reports confirm project code must live on PlayCanvas's servers with no easy local dev environment (playcanvas-comm-8, playcanvas-comm-11, playcanvas-comm-12). The 'Download Apps for Self-hosting' doc refers to exporting built apps, not self-hosting the Editor itself. Missing for 10: an official self-hostable Editor/backend, first-party self-host deployment docs for the full platform, and resolution of the community-confirmed server-lock-in for authoring.

   • [claimed-docs] “Build applications against the Engine directly. Learn how to use the Engine standalone.”
   • [github] “npm install playcanvas”
   • [claimed-docs] “Download Apps for Self-hosting”
   • [community] “When I was working at a mobile game studio, we looked at this as an engine for a project. At the time we decided not to go with it since all…”
   • [community] “I think the engine is open source; but the real appeal is using the real time collab online tool, which is proprietary and had the drawbacks…”
   • [community] “I'd love to be able to use their scene editor offline, uploading assets is a deal breaker.”

   proof ↗⚑ flag

Targets

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

   weight 3 · round to Bevy
   Bevy~partialcommunity5/10

   Docs confirm one Bevy project can target desktop (Windows/macOS/Linux), mobile (iOS/Android) and Web via a single codebase [bevy-docs-6], and community feedback corroborates real-world mobile/web use [bevy-comm-10][bevy-comm-20]. However, there is no evidence—first-party or community—of console export capability, whether direct or via third-party porting partners, which is a key part of the story. Missing for 10: any mention of console targets (Switch/PlayStation/Xbox), official or partner-based console export tooling, or case studies of console shipping.

   • [claimed-docs] “Support for all major platforms: Windows, MacOS, Linux, Web, iOS, Android”
   • [community] “We support low-end devices well! Bevy runs well on iOS currently... Fans spinning is a known issue, but it is generally decoupled from frame…”
   • [community] “Man, you guys really kill it with blog/changelog announcements. Great job! For my use case, Bevy web (and mobile is nice too) support would …”

   proof ↗⚑ flag

   PlayCanvas—none0/10

   Evidence shows PlayCanvas engine and Editor covering web, desktop-via-browser, and self-hosted app export, but there is no mention anywhere in the pack of console export (PlayStation/Xbox/Switch) or partner porting programs. Community commentary consistently frames PlayCanvas as a web-first/WebGL engine with no console story. missing for 10: any documentation of console export or third-party console porting partnership, evidence of desktop/mobile packaging beyond generic 'download apps', console SDK support.

   • [claimed-docs] “Download Apps for Self-hosting”
   • [community] “It is a very nice engine, specially for those focused on Web only as target.”
   • [community] “It's an open source javascript game engine that is kinda like halfway between something like three.js and e.g. Unity—pretty lightweight, but…”

   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 to PlayCanvas
   Bevy~partialcommunity5/10

   Bevy documents official Web platform support and showcases live wasm-compiled examples running in-browser, and a community comment shows real interest in adopting Bevy specifically for web/mobile targets. However, the evidence never mentions WebGPU explicitly, payload size/optimization guidance, or any hands-on report of browser performance/bundle size — the WebGPU 'credible story' half of the claim is unevidenced. Missing for 10: explicit WebGPU backend documentation or roadmap, payload-size/optimization guidance, and independent hands-on confirmation of web build performance.

   • [claimed-docs] “Support for all major platforms: Windows, MacOS, Linux, Web, iOS, Android”
   • [claimed-docs] “Browse bevy examples compiled to wasm and running directly in your browser!”
   • [community] “Man, you guys really kill it with blog/changelog announcements. Great job! For my use case, Bevy web (and mobile is nice too) support would …”

   proof ↗⚑ flag

   PlayCanvas✓fullprobed8/10

   PlayCanvas is explicitly documented as a WebGL/WebGPU engine (probe-1) with a lightweight open-source runtime (npm playcanvas package, MIT license) and community corroboration that it's well-suited to lean web deployment (comm-1, comm-6, comm-13, comm-16) versus bloated alternatives. Missing for 10: no explicit payload-size benchmarks or bundle-size comparisons, and no independent hands-on confirmation of WebGPU parity/performance versus WebGL in production games.

   • [probe] “PROBE llms.txt: HTTP 200 at https://developer.playcanvas.com/llms.txt # PlayCanvas Developer Documentation > PlayCanvas is an open-source W…”
   • [github] “npm install playcanvas”
   • [community] “Unreal is a bloated way to develop WebGPU projects for the web. PlayCanvas is a sensible solution if your target is web.”
   • [community] “It is a very nice engine, specially for those focused on Web only as target.”
   • [community] “THREE.js is very low-level framework, while PlayCanvas additionally to low-level engine access has game framework, which will allow you to c…”
   • [community] “It's an open source javascript game engine that is kinda like halfway between something like three.js and e.g. Unity—pretty lightweight, but…”
   • [probe] “PROBE runtime (recorded 2026-09-15): developer.playcanvas.com serves llms.txt plus the largest llms-full.txt of the arena (2,053,637 bytes o…”

   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 to PlayCanvas
   Bevy—none0/10

   Bevy is distributed exclusively as a Rust crate via crates.io/cargo (bevy-docs-21, bevy-probe-rt-1), not as an npm/JS package; its 'Web' platform support (bevy-docs-6) means compiling to WASM as a game binary, not shipping a tree-shakeable JS library a web developer imports and bundles. No evidence shows npm registry presence, ES-module packaging, or tree-shaking support.

   • [claimed-docs] “Bevy is just a normal Rust dependency. You can either add it to an existing Rust project or create a new one.”
   • [claimed-docs] “Support for all major platforms: Windows, MacOS, Linux, Web, iOS, Android”
   • [probe] “PROBE runtime (recorded 2026-09-15): bevy resolves on crates.io — `cargo search bevy` → 'bevy = "0.19.1" # A refreshingly simple data-driven…”

   proof ↗⚑ flag

   PlayCanvas✓fullprobed8/10

   PlayCanvas engine is published to npm (`npm install playcanvas`, version 2.22.2, ~48k weekly downloads) as a standard ES module library, with docs on using the Engine standalone and scaffolding via create-playcanvas/Vite for standard bundler-based toolchains. Community confirms it integrates with other JS frameworks and modern web-dev workflows (HMR, bundlers), supporting tree-shakable ESM usage. Missing for 10: no explicit documentation or independent confirmation of tree-shaking behavior/bundle-size optimization guidance, and some community reports note setup isn't always straightforward.

   • [github] “npm install playcanvas”
   • [claimed-docs] “Build applications against the Engine directly. Learn how to use the Engine standalone.”
   • [claimed-docs] “Use `create-playcanvas` to scaffold a Vite and TypeScript project for the Engine, React, or Web Components from one of 12 runnable starters.”
   • [probe] “PROBE runtime (recorded 2026-09-15): developer.playcanvas.com serves llms.txt plus the largest llms-full.txt of the arena (2,053,637 bytes o…”
   • [community] “You can use it in conjunction with pretty much any other JS framework available.”
   • [community] “It's certainly not super obvious to setup but there are ways to use PlayCanvas with local setup... with some tinkering you can have hot modu…”

   proof ↗⚑ flag

Iteration

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

   weight 2 · round to PlayCanvas
   Bevy~partialprobed5/10

   Bevy's own docs directly claim 'instant feedback on your changes without app restarts or recompiles' and cite very fast compile times (0.8–3.0s) with a 'fast compiles' config, which matches the story's intent. However, Bevy is a Rust-native engine (not script-based), so this reload speed is achieved via build tooling/dynamic linking rather than a true scripting hot-reload workflow, and there is no independent/hands-on community confirmation of this specific edit-run loop experience — community comments focus on ECS ergonomics, docs quality, and breaking changes instead. Missing for 10: independent/hands-on verification of the hot-reload claim, clarity on scripting vs. Rust recompilation semantics, and community testimony specifically about iteration speed.

   • [claimed-docs] “Get instant feedback on your changes without app restarts or recompiles”
   • [claimed-docs] “With Bevy you can expect 0.8-3.0 seconds with the "fast compiles" configuration”
   • [probe] “PROBE runtime (recorded 2026-09-15): bevy resolves on crates.io — `cargo search bevy` → 'bevy = "0.19.1" # A refreshingly simple data-driven…”

   proof ↗⚑ flag

   PlayCanvas~partialcommunity6/10

   Docs claim live editing lets you tweak materials, positions, and even modify scripts while the application is running, and community reports confirm hot-module-replacement style workflows are achievable with the local sync tooling — but multiple community sources note this setup is 'certainly not super obvious' and historically required 'tinkering,' with one report citing no easy local dev environment as a dealbreaker at the time. missing for 10: first-party benchmark or docs describing built-in near-instant reload latency, and confirmation the friction reported in community threads has been resolved.

   • [claimed-docs] “With live editing, you can tweak materials, adjust positions, and even modify scripts while your application runs.”
   • [community] “It's certainly not super obvious to setup but there are ways to use PlayCanvas with local setup... with some tinkering you can have hot modu…”
   • [community] “When I was working at a mobile game studio, we looked at this as an engine for a project. At the time we decided not to go with it since all…”
   • [community] “I recommend checking out the newly released playcanvas-sync tools which let you map your PlayCanvas project's assets to your local machine's…”

   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 PlayCanvas
   Bevy~partialcommunity5/10

   Bevy uses plain Rust as its 'scripting' layer, and docs plus community comments confirm the ECS API is idiomatic, fully native Rust with no macros/lifetimes needed (bevy-docs-14, bevy-docs-20, bevy-comm-3, bevy-comm-4), which is a strong productivity/API-exposure signal. However, there is no evidence at all of a dedicated debugger or debugging workflow behind this scripting layer, and community feedback flags limited/out-of-date docs and frequent breaking changes as productivity friction (bevy-comm-14, bevy-comm-15, bevy-comm-12). Missing for 10: explicit debugger/debugging-tool evidence, confirmation of full API surface coverage beyond ECS basics, and independent hands-on accounts of debugging Bevy games.

   • [claimed-docs] “Components: Rust structs that implement the Component trait”
   • [claimed-docs] “Unlike other Rust ECS implementations, which often require complex lifetimes, traits, builder patterns, or macros, Bevy ECS uses normal Rust…”
   • [community] “I have to say the API seems to be very pleasant and simple at a glance. Kudos to the author! This pattern is a great example of how Rust ach…”
   • [community] “This is amazing. Seriously: I had a look at nearly every game engine/GUI solution in Rust and this is by far the most thought out, ergonomic…”
   • [community] “I'm put off by the limited docs. I've read the Bevy book, only takes a few minutes, and just like that I'm out of resources to turn to when …”
   • [community] “There's an unofficial complement to the docs... Unfortunately it's somewhat out of date... The effort to keep it up to date is somewhat low …”
   • [community] “Things have started to stabilize, but unless you're willing to get your hands dirty and deal with regular breaking changes, I don't yet reco…”

   proof ↗⚑ flag

   PlayCanvas~partialcommunity6/10

   PlayCanvas scripting uses standard JavaScript/TypeScript (ESM `.mjs` scripts with class syntax) and the full engine can be scripted via `npm install playcanvas`, giving broad API access and a productive, familiar language; community comments (e.g. comm-13) also praise its game-framework layer atop low-level access. However, the evidence pack never explicitly documents a debugger (e.g. browser devtools breakpoints, source maps, or an IDE debug workflow) tied to scripting, and some community feedback flags dev-experience friction (playcanvas-comm-2, playcanvas-comm-3, playcanvas-comm-9) around local/offline workflows that could affect debugging setup. Missing for 10: explicit documentation of a debugger/breakpoint workflow for scripts, and confirmation that the full engine API (not just scripting hooks) is exposed without gaps.

   • [claimed-docs] “ESM Scripts (`.mjs` files) — Modern ES Module-based scripts using class syntax. Recommended for new projects.”
   • [claimed-docs] “ESM Scripts (`.mjs` files) — Modern ES Module-based scripts using class syntax. **Recommended for new projects.**”
   • [claimed-docs] “Build applications against the Engine directly. Learn how to use the Engine standalone.”
   • [github] “npm install playcanvas”
   • [community] “THREE.js is very low-level framework, while PlayCanvas additionally to low-level engine access has game framework, which will allow you to c…”
   • [community] “It's certainly not super obvious to setup but there are ways to use PlayCanvas with local setup... with some tinkering you can have hot modu…”

   proof ↗⚑ flag

Visual

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

   weight 2 · round drawn
   Bevy—none0/10

   Bevy is explicitly a code-first, Rust-based ECS engine (bevy-docs-1, bevy-docs-14, bevy-docs-20, bevy-docs-21) with no mention of a visual scripting system or node-based logic editor anywhere in the evidence; community feedback even discusses concerns about being forced into a code editor, reinforcing the code-only workflow.

   • [claimed-docs] “All engine and game logic uses Bevy ECS, a custom Entity Component System”
   • [claimed-docs] “Components: Rust structs that implement the Component trait”
   • [claimed-docs] “Unlike other Rust ECS implementations, which often require complex lifetimes, traits, builder patterns, or macros, Bevy ECS uses normal Rust…”
   • [claimed-docs] “Bevy is just a normal Rust dependency. You can either add it to an existing Rust project or create a new one.”
   • [community] “The integrated code editor in Godot is actually something I don't like... I hope that Bevy users won't be forced to use the Bevy editor for …”

   proof ↗⚑ flag

   PlayCanvas—none0/10

   Evidence shows PlayCanvas scripting is code-based (ESM/.mjs JavaScript classes) and the Editor supports drag-and-drop scene building and collaboration, but there is no mention of a node-based or visual scripting system for gameplay logic comparable to Blueprints/Bolt that would let a technical artist avoid writing code.

   • [claimed-docs] “ESM Scripts (`.mjs` files) — Modern ES Module-based scripts using class syntax. Recommended for new projects.”
   • [claimed-docs] “Want drag-and-drop scene building, real-time collaboration, or prefer visual tools over code”
   • [claimed-docs] “ESM Scripts (`.mjs` files) — Modern ES Module-based scripts using class syntax. **Recommended for new projects.**”

   proof ↗⚑ flag