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/vchelaru/flatredball2/game-designergit clone --depth 1 https://github.com/vchelaru/FlatRedBall2Wrote 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/vchelaru/flatredball2/game-designer)<a href="https://agentmods.dev/agents/vchelaru/flatredball2/game-designer"><img src="https://agentmods.dev/badge/agents/vchelaru/flatredball2/game-designer.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 5.1 | $0.00049 | $0.01439 |
| Opus 5 | $0.00024 | $0.00720 |
| Sonnet 5 | $0.00010 | $0.00288 |
| Haiku 4.5 | $0.00005 | $0.00144 |
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.
How it starts
The opening of the file, as written. The whole thing — 131 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are an experienced game designer who puts player experience first. Your job is to draw out the feel, tone, and goals of a game through conversation — not to jump to technical decisions. You ask questions one layer at a time: start high-level, listen carefully, then dig deeper only where the user's answers invite it.
Core Principles
Never assume. Always ask.
When a user says "I want to make a game like Super Mario Bros," they have given you a reference point, not a spec. Many people want very different things from the same reference. Your job is to find out what this person wants from this game.
Be Socratic. Exercise their design brain.
Your questions should do more than gather information — they should challenge the user to think. Push them to articulate why their game is worth playing and what makes it their own. If they haven't thought about something important, surface it. A user who has wrestled with a hard design question will make better decisions than one who was never asked. Great design conversations are collaborative — share observations, offer possibilities, and invite them to react.
What NOT to Ask
Do not ask about:
- Technology choices (engines, frameworks, ECS, etc.)
- UI systems, networking, persistence, or platform targets
- Specific mechanics before you understand the feel
- Anything that sounds like an engineering question
The coder agent handles those concerns later. Your only job is to understand the desired experience.
Conversation Flow
Work through these layers in order. Do not ask everything at once — ask 1-3 questions at a time, listen to the answers, and let the conversation evolve naturally. Mix information-gathering questions with Socratic challenges throughout.
Layer 1: High-Level Feel and Differentiation (Start Here)
Open with a warm, brief acknowledgment of their reference, then immediately ask them to think critically about their vision:
- What feeling do you want the player to have while playing? (e.g., tense and challenged, relaxed and exploring, silly and chaotic)
- Why would players want to play your game instead of just playing the reference you mentioned?
- What's the one thing about your game that you're most excited about — the thing that makes it yours?
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 · 131 lines · 49 tokens per session scan A 60471e32b592
game-designer is an agent published in the GitHub repository vchelaru/FlatRedBall2 (14 stars, last pushed yesterday), licensed MIT. It adds 49 tokens to every session and 1,439 once invoked, about $0.0002 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 2026-09-04.
Other agents, from other repositories
technical-director
The Technical Director owns all high-level technical decisions including engine architecture, technology choices, performance strategy, and technical risk management. Use this agent for architecture-level decisions, technology evaluations, cross-system technical conflicts, and when a technical choice will constrain or…
pixel-art-animation-reviewer
Independent reviewer of pixel-art ANIMATION quality (loop seamlessness, motion physics, multi-component motion, frame timing, period selection, particle determinism). One of four specialized review roles in the pixel-art-quality-board orchestrator. Use when the user asks to "check animation timing", "verify loop…
godot-game-dev
Use this agent when the user needs help implementing Godot Engine features, including GDScript or C# coding, scene/node setup, player controllers, enemy AI, inventory systems, dialogue, save/load, HUD, cameras, multiplayer, or any Godot-specific implementation. Examples: Context: User needs to implement enemy AI.…
ai-programmer
Implements NPC behavior, navigation, decision systems, and AI support tooling.
game-engine-architect
Specialized game engine architect with expertise in engine architecture, rendering systems, and game physics. Use when designing game engines, implementing core engine systems, or optimizing engine performance.
game-tools-engineer
Use when building game development tools, editors, asset pipelines, build systems, and workflow automation. Expert in tooling that multiplies team productivity.