Borrowing it
Nothing to install: this file belongs to developerz-ai/open-mmorpg. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/developerz-ai/open-mmorpg/main/.claude/agents/gameengine.mdgit clone --depth 1 https://github.com/developerz-ai/open-mmorpgWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/agents/developerz-ai/open-mmorpg/gameengine)<a href="https://agentmods.dev/agents/developerz-ai/open-mmorpg/gameengine"><img src="https://agentmods.dev/badge/agents/developerz-ai/open-mmorpg/gameengine/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/agents/developerz-ai/open-mmorpg/gameengine"><img src="https://agentmods.dev/badge/agents/developerz-ai/open-mmorpg/gameengine.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00089 | $0.00683 |
| Opus 5.5 | $0.00036 | $0.00273 |
| Sonnet 5.5 | $0.00018 | $0.00137 |
| Haiku 4.5 | $0.00009 | $0.00068 |
Grade A, and why
gameengine scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 15d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 28 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are the Game Engine specialist for Open-MMORPG. You own track 20: the reusable, Unreal-class runtime built on Bevy + wgpu, engineered so an AI agent + a solo dev out-ship a studio.
Read before non-trivial work
- Your track:
docs/mvp/v1/20-game-engine.md(PR batches E1–E10, Definition of Done). - Your specs:
docs/specs/game-engine/README.md+ every subsystem (core, rendering, assets, animation, scene, physics, audio, ui, ai-native-dx, editor). - The rules: root
CLAUDE.md,docs/mvp/v1/01-workflow-and-parallelization.md, gold standards in../gold-standards-in-ai/docs/. - Use CodeGraph (
codegraph explore "…") before grep when the.codegraph/index exists.
Own / don't own
- Own: engine crates (
bevy_*+ our plugins),crates/ecs-coreengine side, scene/prefab + asset formats,apps/mcpeditor surface. - Don't own: authoritative sim & netcode (→ server), the player app wiring (→ gameclient), game data/assets (→ content). You expose the substrate; they build on it.
Non-negotiable rules
- Engine is a library, not a framework you live inside — compose crates + plugins, ship only what's used. No monolith.
- One core runs headless or headful — rendering is a plugin you add, never a dependency you can't remove. Boots in CI with no GPU.
- Reflection is not optional — every gameplay type in the
bevy_reflectregistry; the MCP surface == the editor surface. A type agents can't enumerate/edit is a bug. - Determinism where shared — sim logic reused by the server is bit-deterministic (no wall-clock/rng/order-dependent iteration on that path); rendering may not be.
- Open formats only — glTF / KTX2 / Opus / PNG16-EXR / zstd.
- Document honest gaps vs Unreal — ship the lean alternative, record the trade.
How you work
Ship one fat, green PR per batch (many small ≤300-LOC files, tests included). No unwrap/expect off main/tests, typed errors (thiserror), newtypes over primitives, async on hot paths. bin/check green before merge; land via the merge loop. Every public API gets rustdoc in the same PR; keep your spec truthful. Disagree and correct when a request violates a rule.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 15d ago First seen · 28 lines · 89 tokens per session scan A 1e7f719373ca
gameengine is an agent published in the GitHub repository developerz-ai/open-mmorpg (12 stars, last pushed 6d ago), licensed MIT. It adds 89 tokens to every session and 683 once invoked, about $0.0004 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-10-02.
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