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 instructions/mcdxai/minecraft-dev-mcp/claude-mdgit clone --depth 1 https://github.com/MCDxAI/minecraft-dev-mcpWrote 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/instructions/mcdxai/minecraft-dev-mcp/claude-md)<a href="https://agentmods.dev/instructions/mcdxai/minecraft-dev-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/mcdxai/minecraft-dev-mcp/claude-md.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 | $0.05815 | $0.05815 |
| Opus 5 | $0.02908 | $0.02908 |
| Sonnet 5 | $0.01163 | $0.01163 |
| Haiku 4.5 | $0.00581 | $0.00581 |
Grade A, and why
minecraft-dev-mcp CLAUDE.md 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 4d 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 — 496 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Claude Code Context - Minecraft Dev MCP
This document provides essential context for working with the Minecraft Dev MCP codebase.
Project Overview
This is a Model Context Protocol (MCP) server that provides AI assistants with access to decompiled Minecraft source code, registry data, and modding tools. It enables LLMs to help developers with Minecraft mod development by providing accurate, version-specific source code and game data.
Release Status
- Phase 1 & 2 complete (core services, remap/decompile/search/compare) as of 2025-12-06; 29 integration tests pass end-to-end.
- Phase 3 complete (third-party mod analysis) as of 2025-12-15; includes full mod decompilation, search, and indexing capabilities with WSL support.
Architecture
Core Services (src/services/)
-
version-manager.ts - Downloads and manages Minecraft client/server JARs from Mojang
getVersionJar()- Downloads client JAR (for remapping/decompilation)getServerJar()- Downloads server JAR (for registry extraction)- Caches JARs in AppData/config directory
-
mapping-service.ts - Downloads and manages mappings (Yarn, Mojmap, Intermediary)
- Yarn: Community mappings (best for mod development)
- Mojmap: Official Mojang mappings
- Intermediary: Fabric's stable intermediate mapping format
-
remap-service.ts - Remaps obfuscated Minecraft JARs using mappings
- Uses tiny-remapper Java tool
- Converts obfuscated names → human-readable names
- Yarn requires 2-step remapping: obfuscated → intermediary → yarn
-
decompile-service.ts - Decompiles remapped JARs to Java source
- Uses VineFlower decompiler
- Produces readable Java source code
- Caches decompiled sources for reuse
-
registry-service.ts - Extracts Minecraft registry data (blocks, items, entities, etc.)
- CRITICAL: Must use SERVER JAR, not client JAR
- Uses Minecraft's built-in data generator (
--reportsflag) - Handles both modern (1.18+) and legacy (<1.18) formats
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.
- 4d ago First seen · 496 lines · 5,815 tokens per session scan A b5e1e4feba4b
minecraft-dev-mcp CLAUDE.md is an instructions file published in the GitHub repository MCDxAI/minecraft-dev-mcp (35 stars, last pushed 28d ago), licensed MIT. It adds 5,815 tokens to every session, about $0.0291 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 2026-08-30.
Other instructions, from other repositories
better-godot-mcp CLAUDE.md
Instructions for n24q02m/better-godot-mcp, covering claude.md - better-godot-mcp, commands, setup, lint & type check and fix.
better-godot-mcp AGENTS.md
Instructions for n24q02m/better-godot-mcp, covering agents.md - better-godot-mcp, build / lint / test commands, run a single test file, run a single test by name and mise shortcuts.
minecraft-java-fabric-claude-plugin CLAUDE.md
Instructions for chapmanjw/minecraft-java-fabric-claude-plugin, covering claude.md, commands, architecture, the three-tier, no-trivial model (0.9.0) and terrain core (tools/terrain/).
mcp-steam CLAUDE.md
Claude Code instructions for obrien-matthew/mcp-steam, a project described as: MCP server for Steam -- gaming library, achievements, stats, and store discovery for Claude and other LLM agents.
Cities2-MCP AGENTS.md
Instructions for mayor-modder/Cities2-MCP, covering agent rules, workspace safety, commit and pr safety, public-facing writing and merge and release gates.
bray AGENTS.md
AGENTS.md instructions for forgesworn/bray, covering agents.md — nostr-bray, what this is, build & test, architecture and tool groups.