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 skills add merlinhu1/codex-game-studio --skill cgs-prototypegit 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/skills/merlinhu1/codex-game-studio/cgs-prototype)<a href="https://agentmods.dev/skills/merlinhu1/codex-game-studio/cgs-prototype"><img src="https://agentmods.dev/badge/skills/merlinhu1/codex-game-studio/cgs-prototype/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/skills/merlinhu1/codex-game-studio/cgs-prototype"><img src="https://agentmods.dev/badge/skills/merlinhu1/codex-game-studio/cgs-prototype.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 | $0.00042 | $0.00585 |
| Opus 5.5 | $0.00017 | $0.00234 |
| Sonnet 5.5 | $0.00008 | $0.00117 |
| Haiku 4.5 | $0.00004 | $0.00059 |
Grade A, and why
cgs-prototype 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 1mo 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.
What it actually says
Codex Game Studio Prototype
Use this skill for prototype work in Template Game.
Objective
Build or plan a throwaway concept prototype around a falsifiable design hypothesis and cleanup boundary.
Inputs
- AGENTS.md
- .codex/studio.json
- task-relevant files named by the user or task record
- design/gdd.md
- production/session-state/active.md
- tests/
- .codex/workflows/prototype.md
Arguments
- Objective or user request.
- Target files, scenes, assets, or docs.
- Constraints, deadlines, acceptance criteria, and verification command when known.
Procedure
- Clarify the requested build or plan a throwaway concept prototype around a falsifiable design hypothesis and cleanup boundary. and identify the current project stage.
- Collect evidence for Prototype Hypothesis, Throwaway Boundary, Success Signal.
- Run or define the focused validation loop before reporting conclusions.
- Produce the requested artifact or review with clear file paths and verification evidence.
Write Targets
- tests/
- production/session-state/
- prototypes/
Output Contract
- Summary
- Prototype Hypothesis
- Throwaway Boundary
- Success Signal
- Cleanup
- Risks
- Changed files or proposed files
- Verification evidence
- Next owner or decision
Quality Gates
- Prototype Hypothesis
- Throwaway Boundary
- Success Signal
- Cleanup
- Scope remains bounded to the current task and project stage.
- Report labels unverified assumptions separately from evidence.
Decision Gates
- Continue only when the expected output can be verified or clearly labeled as a plan.
- Escalate to producer or qa-playtester when scope, ownership, or acceptance evidence is ambiguous.
- Stop before broad rewrites, generated prompt mirrors, or hidden lifecycle behavior.
Handoff
Report changed files, verification evidence, remaining risks, and the next owner or decision. Do not imply hidden hooks or autonomous background work.
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 1mo ago First seen · 82 lines · 42 tokens per session scan A 5efb7eb304e9
cgs-prototype is a skill published in the GitHub repository merlinhu1/codex-game-studio (74 stars, last pushed 2mo ago), licensed MIT. It adds 42 tokens to every session and 585 once invoked, about $0.0002 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 2026-08-30.
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