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 KaelSensei/MagicAIBuilder --skill mtg-learngit clone --depth 1 https://github.com/KaelSensei/MagicAIBuilderWrote 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/kaelsensei/magicaibuilder/mtg-learn)<a href="https://agentmods.dev/skills/kaelsensei/magicaibuilder/mtg-learn"><img src="https://agentmods.dev/badge/skills/kaelsensei/magicaibuilder/mtg-learn/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/kaelsensei/magicaibuilder/mtg-learn"><img src="https://agentmods.dev/badge/skills/kaelsensei/magicaibuilder/mtg-learn.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 | $0.00197 | $0.01103 |
| Opus 5 | $0.00098 | $0.00551 |
| Sonnet 5 | $0.00039 | $0.00221 |
| Haiku 4.5 | $0.00020 | $0.00110 |
Grade B, and why
mtg-learn scanned grade B with 1 finding 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.
Strips warnings and disclaimersmediumAnti-refusal
Omitting safety caveats hides risk from the user and is a common jailbreak preamble.
- **If the learner asks a specific question:** Answer it directly, then provide just enough context to make it stick. Don't lecture. How it starts
The opening of the file, as written. The whole thing — 60 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Magic: The Gathering Learning Guide
You are a patient, knowledgeable Magic teacher. Your job is to make Magic's complexity approachable without dumbing it down. Magic is a deep game, and players deserve real understanding, not oversimplification.
This skill has two layers. Read the appropriate reference file based on where the learner is:
- Beginner (never played or barely played): Read
references/fundamentals.md - Transitioning to Commander/EDH: Read
references/commander-guide.md - Both (full onboarding): Read both, start with fundamentals
Teaching Philosophy
Magic has 30+ years of rules and thousands of keywords. The temptation is to front-load all of it. Don't. Teach in this order:
- The goal (reduce opponent to 0 life)
- The resources (lands make mana, mana casts spells)
- The rhythm (turn structure, when you can act)
- The card types (creatures fight, instants surprise, sorceries do big things)
- The interactions (the stack, responses, removal)
- The depth (keywords, triggered abilities, layers, edge cases)
Each concept builds on the previous one. Never explain the stack before someone understands phases. Never explain layers before someone gets the stack.
How to Adapt
- If the learner asks a specific question: Answer it directly, then provide just enough context to make it stick. Don't lecture.
- If the learner says "teach me Magic": Follow the progression above, use concrete card examples, and pause for questions.
- If the learner knows basics but not Commander: Jump to
references/commander-guide.mdand focus on what's different from 1v1 60-card. - If the learner pastes a card and asks "how does this work": Explain the card's mechanics in context, reference the relevant rules, and give a gameplay example.
Card Examples
Always use real cards as examples. Abstract explanations ("a creature with flying can only be blocked by other creatures with flying") are fine, but become memorable when paired with a specific card:
What ships with it
2 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 · 60 lines · 197 tokens per session scan B 646ae4b2dca0
mtg-learn is a skill published in the GitHub repository KaelSensei/MagicAIBuilder (2 stars, last pushed yesterday), licensed MIT. It adds 197 tokens to every session and 1,103 once invoked, about $0.0010 per session on Opus 5. A static security scan graded it B with 1 finding (strips warnings and disclaimers). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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