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 medy-gribkov/arcana --skill level-designgit clone --depth 1 https://github.com/medy-gribkov/arcanaWrote 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/medy-gribkov/arcana/level-design)<a href="https://agentmods.dev/skills/medy-gribkov/arcana/level-design"><img src="https://agentmods.dev/badge/skills/medy-gribkov/arcana/level-design/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/medy-gribkov/arcana/level-design"><img src="https://agentmods.dev/badge/skills/medy-gribkov/arcana/level-design.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 | $0.00023 | $0.03533 |
| Opus 5 | $0.00012 | $0.01767 |
| Sonnet 5 | $0.00005 | $0.00707 |
| Haiku 4.5 | $0.00002 | $0.00353 |
Grade A, and why
level-design 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 9d 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.
How it starts
The opening of the file, as written. The whole thing — 396 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Level Design
Level Design Philosophy
┌─────────────────────────────────────────────────────────────┐
│ LEVEL DESIGN PILLARS │
├─────────────────────────────────────────────────────────────┤
│ 1. FLOW: Guide the player naturally through space │
│ 2. PACING: Control intensity and rest moments │
│ 3. DISCOVERY: Reward exploration and curiosity │
│ 4. CLARITY: Player always knows where to go │
│ 5. CHALLENGE: Skill tests that teach and satisfy │
└─────────────────────────────────────────────────────────────┘
Level Structure Patterns
LINEAR LEVEL:
┌─────────────────────────────────────────────────────────────┐
│ [Start] → [Tutorial] → [Challenge] → [Boss] → [End] │
│ │
│ PROS: Easy to pace, clear direction │
│ CONS: Limited replay value, less exploration │
│ BEST FOR: Story-driven games, action games │
└─────────────────────────────────────────────────────────────┘
HUB & SPOKE:
┌─────────────────────────────────────────────────────────────┐
│ [Level A] │
│ ↑ │
│ [Level B] ← [HUB] → [Level C] │
│ ↓ │
│ [Level D] │
│ │
│ PROS: Player choice, non-linear progression │
│ CONS: Can feel disconnected │
│ BEST FOR: RPGs, Metroidvanias, open-world │
└─────────────────────────────────────────────────────────────┘
METROIDVANIA:
┌─────────────────────────────────────────────────────────────┐
│ ┌───┐ ┌───┐ ┌───┐ │
│ │ A │───│ B │───│ C │ (locked: need ability X) │
│ └─┬─┘ └───┘ └───┘ │
│ │ │ │
│ ┌─┴─┐ ┌─┴─┐ │
│ │ D │───│ E │ (grants ability X) │
│ └───┘ └───┘ │
│ │
│ PROS: Rewarding exploration, ability gating │
│ CONS: Can get lost, backtracking tedium │
│ BEST FOR: Exploration games, 2D platformers │
└─────────────────────────────────────────────────────────────┘
What ships with it
3 files 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.
- 9d ago First seen · 396 lines · 23 tokens per session scan A 5fddec1a422b
level-design is a skill published in the GitHub repository medy-gribkov/arcana (1 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 23 tokens to every session and 3,533 once invoked, about $0.0001 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 2026-08-31.
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