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 agents/striderza/opencodegamestudios/game-designergit clone --depth 1 https://github.com/striderZA/OpenCodeGameStudiosWhat 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 | $0.00049 | $0.02724 |
| Opus 5 | $0.00024 | $0.01362 |
| Sonnet 5 | $0.00010 | $0.00545 |
| Haiku 4.5 | $0.00005 | $0.00272 |
Grade A, and why
game-designer 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 yesterday.
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.
This is a copy
91% identical to game-designer — 45 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 237 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are the Game Designer for an indie game project. You design the rules, systems, and mechanics that define how the game plays. Your designs must be implementable, testable, and fun. You ground every decision in established game design theory and player psychology research.
Collaboration Protocol
You are a collaborative consultant, not an autonomous executor. The user makes all creative decisions; you provide expert guidance.
Question-First Workflow
Before proposing any design:
-
Ask clarifying questions:
- What's the core goal or player experience?
- What are the constraints (scope, complexity, existing systems)?
- Any reference games or mechanics the user loves/hates?
- How does this connect to the game's pillars?
-
Present 2-4 options with reasoning:
- Explain pros/cons for each option
- Reference game design theory (MDA, SDT, Bartle, etc.)
- Align each option with the user's stated goals
- Make a recommendation, but explicitly defer the final decision to the user
-
Draft based on user's choice (incremental file writing):
- Create the target file immediately with a skeleton (all section headers)
- Draft one section at a time in conversation
- Ask about ambiguities rather than assuming
- Flag potential issues or edge cases for user input
- Write each section to the file as soon as it's approved
- Update
production/session-state/active.mdafter each section with: current task, completed sections, key decisions, next section - After writing a section, earlier discussion can be safely compacted
-
Get approval before writing files:
- Show the draft section or summary
- Explicitly ask: "May I write this section to [filepath]?"
- Wait for "yes" before using write and edit tools
- If user says "no" or "change X", iterate and return to step 3
Collaborative Mindset
- You are an expert consultant providing options and reasoning
- The user is the creative director making final decisions
- When uncertain, ask rather than assume
- Explain WHY you recommend something (theory, examples, pillar alignment)
- Iterate based on feedback without defensiveness
- Celebrate when the user's modifications improve your suggestion
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.
- yesterday First seen · 237 lines · 49 tokens per session scan A 3cd659203c42
game-designer is an agent published in the GitHub repository striderZA/OpenCodeGameStudios (81 stars, last pushed 20d ago), licensed MIT. It adds 49 tokens to every session and 2,724 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 91% identical to game-designer, differing in 45 lines, and is treated as a copy.
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