Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add instructions/merlinhu1/codex-game-studio/agents-mdgit clone --depth 1 https://github.com/merlinhu1/codex-game-studioWrote 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/instructions/merlinhu1/codex-game-studio/agents-md)<a href="https://agentmods.dev/instructions/merlinhu1/codex-game-studio/agents-md"><img src="https://agentmods.dev/badge/instructions/merlinhu1/codex-game-studio/agents-md.svg" alt="Measured on agentmods" 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 | $0.00945 | $0.00945 |
| Opus 5 | $0.00473 | $0.00473 |
| Sonnet 5 | $0.00189 | $0.00189 |
| Haiku 4.5 | $0.00094 | $0.00094 |
Grade A, and why
codex-game-studio AGENTS.md 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 today.
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 — 79 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Codex Game Studio Template
This repository is a game-studio template. The visible Codex agents, workflows, and skills in this checkout are the operating surface for game-development work.
Project Goal
Build and evolve an indie game in this repository using bounded Codex game-studio roles, reviewable workflow files, and explicit validation evidence.
Engine
Choose and record the active engine in .codex/studio.json during project setup. Supported engine tracks include Godot, Unity, and Unreal.
Commands
- Configure project state:
./codex-game-studio init --non-interactive --name "<Game>" --engine <godot|unity|unreal> --mode <design|prototype|development> - Validate repository/template and initialized project state:
./codex-game-studio validate - Run a role:
./codex-game-studio run <role> "<task>" - Inspect workflow status:
./codex-game-studio status
Context Bootstrap
Before broad inspection, use compact context helpers when available, then read only surfaced files and explicit task targets:
./codex-game-studio context studio./codex-game-studio context task "<task>"./codex-game-studio context role <role-id>./codex-game-studio context workflow <workflow-id>./codex-game-studio context changed
Model Routing
- Prompt surfaces declare both a concrete model and a reasoning effort; runtime derives only the model tier from the centralized model policy.
- Choose the model family by capability and blast radius: Sol for difficult/high-risk architecture, security, release, or cross-system decisions; Terra for bounded implementation, QA, docs, and production work; Luna for simple, repetitive, mechanical, or objectively verifiable work.
- Choose reasoning effort independently for each prompt surface. Valid combinations include Luna/medium for cheap-but-careful review, Terra/low for bounded routine work, Terra/high for difficult implementation, and Sol/medium when Sol capability is useful without maximum reasoning.
- Explicit user or task-tier overrides change the model family but preserve the selected surface's reasoning effort unless an escalation policy deliberately raises it.
- Designated fallback models are fixed by family: Sol to GPT-5.5, Terra to GPT-5.4, and Luna to GPT-5.4-mini; fallback execution keeps the selected surface effort.
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.
- today First seen · 79 lines · 945 tokens per session scan A 8eacaf008659
codex-game-studio AGENTS.md is an instructions file published in the GitHub repository merlinhu1/codex-game-studio (53 stars, last pushed 25d ago), licensed MIT. It adds 945 tokens to every session, about $0.0047 per session on Opus 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 2026-09-03.
Other instructions, from other repositories
yume CLAUDE.md
Instructions for kamwoh/yume, covering yume (夢) — json-driven game framework on godot, quick start, framework structure, how the engine works and tick rate is the engine's heartbeat (2026-05-16).
everything-game-dev-code copilot-instructions.md
Copilot instructions for MRCalderon3D/everything-game-dev-code, covering github copilot repository instructions, repository intent, how to navigate the repository, working rules and repository maintenance.
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.