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 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/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/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="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 | $0.00060 | $0.01136 |
| Opus 5.5 | $0.00024 | $0.00454 |
| Sonnet 5.5 | $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 1mo 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.
- 1mo 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 (8 stars, last pushed 1mo ago), licensed MIT. It adds 60 tokens to every session and 1,136 once invoked, about $0.0002 per session on Opus 5.5. 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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