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/chapmanjw/minecraft-java-fabric-claude-plugin/setup-modnpx skills add chapmanjw/minecraft-java-fabric-claude-plugin --skill setup-modgit clone --depth 1 https://github.com/chapmanjw/minecraft-java-fabric-claude-pluginWrote 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/chapmanjw/minecraft-java-fabric-claude-plugin/setup-mod)<a href="https://agentmods.dev/skills/chapmanjw/minecraft-java-fabric-claude-plugin/setup-mod"><img src="https://agentmods.dev/badge/skills/chapmanjw/minecraft-java-fabric-claude-plugin/setup-mod.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 | $0.00060 | $0.01136 |
| Opus 5 | $0.00030 | $0.00568 |
| Sonnet 5 | $0.00012 | $0.00227 |
| Haiku 4.5 | $0.00006 | $0.00114 |
Grade A, and why
setup-mod 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 3d 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 — 119 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Install the MCP mod + Fabric API (Step 2 of 4)
This is Phase 2 of the four-phase Minecraft Java MCP setup. It assumes
Phase 1 (setup-fabric) is done: Fabric is installed and the mods/ folder
exists. You should have, written down:
- the chosen Minecraft version (e.g.
26.2); - the mods-folder path (single-player) or the
<server>root with itsmods/folder (dedicated server).
If either is missing, get it before continuing. Work interactively — confirm each download before moving on.
What you're installing
The MCP server is delivered as a Fabric mod. It needs exactly two jars in
mods/, both matching the same Minecraft version:
- The MCP mod —
minecraft-fabric-mcp-<modver>+<mc-version>.jar. - Fabric API — the mod's only dependency.
Match the Minecraft version on both jars. A jar built for
26.1.2will not load on1.21.11, and vice versa. The version suffix after the+must equal the version chosen in Phase 1.
Step 1 — Download the MCP mod jar
From the mod's releases: https://github.com/chapmanjw/minecraft-java-fabric-mcp-server/releases
Pick the asset whose filename ends in +<your-mc-version>.jar — e.g.
minecraft-fabric-mcp-1.0.1+26.2.jar for Minecraft 26.2. Pin to a specific
release tag rather than tracking latest, so the version stays in lockstep
with Minecraft and Fabric API.
Step 2 — Download the matching Fabric API jar
From Modrinth: https://modrinth.com/mod/fabric-api/versions
Filter by your Minecraft version and download the Fabric API jar for it — e.g.
fabric-api-0.155.2+26.2.jar. Its Minecraft version must match exactly.
The mod jar declares an EXACT
depends.minecraft, so a jar built for one Minecraft version is refused at load on any other — you get a clear loader error rather than a crash later. Do not mix versions across the two jars.
Step 3 — Put both jars in mods/
Copy both jars into the mods/ folder from Phase 1.
Single-player — the platform path:
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.
- 3d ago First seen · 119 lines · 60 tokens per session scan A 260a351a3d1d
setup-mod is a skill published in the GitHub repository chapmanjw/minecraft-java-fabric-claude-plugin (6 stars, last pushed 6d ago), licensed MIT. It adds 60 tokens to every session and 1,136 once invoked, about $0.0003 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.
Other skills, from other repositories
minecraft-dev
Use this skill whenever the user wants to look up Minecraft source, mod source, mod loader source, mappings, registries, versions, version differences, access transformers, mixin information, documentation, or code search results with minecraft-dev-cli. Also use it for Fabric, Forge, Quilt, and NeoForge source lookups.
ashfox
Create, edit, review, animate, and export game-ready low-poly assets in the ashfox web workbench through an AI agent. Use for low-poly modeling, deterministic textures and UVs, rigs, idle or motion animation, GLB, Bedrock, or GeckoLib exports, and Blockbench-free asset production.
1211-neoforge-modding
Minecraft 1.21.1 NeoForge Moddingに関する開発支援。Modの新規作成、Block/Item/Entityの追加、 DataGen、ネットワーク処理（Payload System）、レシピ・進捗・ルートテーブルの生成、 Capability/Data Component/Data Attachmentの実装、クラッシュ対応など。 Minecraft 1.21.1 NeoForge Moddingに関するタスクや、ModDevGradleのセットアップ、 Registry/Event/sidednessに関する質問があった際に使用する。.
1201-forge-modding
Minecraft 1.20.1 Forge Moddingに関する開発支援。Modの新規作成、Block/Item/Entityの追加、 DataGen、ネットワーク処理、レシピ・進捗・ルートテーブルの生成、Capabilityの実装、 クラッシュ対応など。Minecraft 1.20.1 Moddingに関するタスクや、Gradle/MDKのセットアップ、 Registry/Event/sidednessに関する質問があった際に使用する。.
1201-mods-exsample
Minecraft 1.20.1 Forge Moddingにおける実践的な実装パターン集。 エネルギー・GUI・ネットワーク・マルチブロック・レシピ・レンダリング・ スペル/AI/スクリプトなどの設計パターンを、17の主要Modの実装から抽出して解説。 Addon作成に使える部分は各Modトピックとして維持しつつ、Modに依存しない アーキテクチャ知識として整理する。.
1211-mods-exsample
Minecraft 1.21.1 NeoForge Moddingにおける実践的な実装パターン集。 エネルギー・GUI・ネットワーク・マルチブロック・レシピ・レンダリング・ スペル/AI/スクリプトなどの設計パターンを、16の主要Modの実装から抽出して解説。 Forge 1.20.1 → NeoForge 1.21.1 の移行差分（Data Component・Payload System・ Data Attachment）を加味したNeoForge版パターン集。.