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 skills/bullish0x/gamestudio/startnpx skills add bullish0x/GameStudio --skill startgit clone --depth 1 https://github.com/bullish0x/GameStudioWrote 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/bullish0x/gamestudio/start)<a href="https://agentmods.dev/skills/bullish0x/gamestudio/start"><img src="https://agentmods.dev/badge/skills/bullish0x/gamestudio/start.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 | $0.00022 | $0.03196 |
| Opus 5 | $0.00011 | $0.01598 |
| Sonnet 5 | $0.00004 | $0.00639 |
| Haiku 4.5 | $0.00002 | $0.00320 |
Grade A, and why
start 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 2d 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.
This is a copy
95% identical to start — 5 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 — 245 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Guided Onboarding
This skill writes one file: production/review-mode.txt (review mode config set in Phase 3b).
This skill is the entry point for new users. It does NOT assume you have a game idea, an engine preference, or any prior experience. It asks first, then routes you to the right workflow.
Phase 1: Detect Project State
Before asking anything, silently gather context so you can tailor your guidance. Do NOT show these results unprompted — they inform your recommendations, not the conversation opener.
Check:
- Engine configured? Read
.agents/docs/technical-preferences.md. If the Engine field contains[TO BE CONFIGURED], the engine is not set. - Game concept exists? Check for
design/gdd/game-concept.md. - Source code exists? Glob for source files in
src/(*.gd,*.cs,*.cpp,*.h,*.rs,*.py,*.js,*.ts). - Prototypes exist? Check for subdirectories in
prototypes/. - Design docs exist? Count markdown files in
design/gdd/. - Production artifacts? Check for files in
production/sprints/orproduction/milestones/.
Store these findings internally to validate the user's self-assessment and tailor recommendations.
Phase 2: Ask Where the User Is
This is the first thing the user sees. Use AskUserQuestion with these exact options so the user can click rather than type:
- Prompt: "Welcome to GameStudio! Before I suggest anything, I'd like to understand where you're starting from. Where are you at with your game idea right now?"
- Options:
A) No idea yet— I don't have a game concept at all. I want to explore and figure out what to make.B) Vague idea— I have a rough theme, feeling, or genre in mind (e.g., "something with space" or "a cozy farming game") but nothing concrete.C) Clear concept— I know the core idea — genre, basic mechanics, maybe a pitch sentence — but haven't formalized it into documents yet.D) Existing work— I already have design docs, prototypes, code, or significant planning done. I want to organize or continue the work.
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.
- 2d ago First seen · 245 lines · 22 tokens per session scan A 0c16108f04d6
start is a skill published in the GitHub repository bullish0x/GameStudio (10 stars, last pushed 2mo ago), licensed MIT. It adds 22 tokens to every session and 3,196 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 95% identical to start, differing in 5 lines, and is treated as a copy.
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