Borrowing it
Nothing to install: this file belongs to st-VALVe/mcp-unity. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/st-VALVe/mcp-unity/main/CLAUDE.mdgit clone --depth 1 https://github.com/st-VALVe/mcp-unityWrote 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/st-valve/mcp-unity/claude-md)<a href="https://agentmods.dev/instructions/st-valve/mcp-unity/claude-md"><img src="https://agentmods.dev/badge/instructions/st-valve/mcp-unity/claude-md/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/instructions/st-valve/mcp-unity/claude-md"><img src="https://agentmods.dev/badge/instructions/st-valve/mcp-unity/claude-md.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 | $0.01242 | $0.01242 |
| Opus 5.5 | $0.00497 | $0.00497 |
| Sonnet 5.5 | $0.00248 | $0.00248 |
| Haiku 4.5 | $0.00124 | $0.00124 |
Grade A, and why
mcp-unity 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 2mo 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- mcp-unity CLAUDE.md — 100% identical, 2 lines differ
How it starts
The opening of the file, as written. The whole thing — 133 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
Project Overview
MCP Unity exposes Unity Editor capabilities to MCP-enabled clients (Cursor, Windsurf, Claude Code, Codex CLI, GitHub Copilot) through a two-tier architecture:
- Unity Editor (C#): WebSocket server inside Unity that executes tools/resources
- Node.js Server (TypeScript): MCP stdio server that bridges AI clients to Unity via WebSocket
Data flow: MCP Client ⇄ (stdio) ⇄ Node Server (Server~/src/index.ts) ⇄ (WebSocket) ⇄ Unity Editor (Editor/UnityBridge/McpUnityServer.cs)
Build & Development Commands
Node.js Server (Server~/)
npm install # Install dependencies
npm run build # Compile TypeScript to build/
npm run watch # Watch mode compilation
npm start # Run server (node build/index.js)
npm test # Run Jest tests (uses --experimental-vm-modules)
npm run test:watch # Watch mode testing
npm run inspector # Launch MCP Inspector for debugging
Unity Side
- Build/Test via Unity Editor
- Tools > MCP Unity > Server Window for configuration
- Window > General > Test Runner for EditMode tests
Key Directories
Editor/ # Unity Editor package (C#)
├── Tools/ # MCP tools (inherit McpToolBase)
├── Resources/ # MCP resources (inherit McpResourceBase)
├── Services/ # TestRunnerService, ConsoleLogsService
├── UnityBridge/ # WebSocket server + message routing
│ ├── McpUnityServer.cs # Singleton managing server lifecycle
│ └── McpUnitySocketHandler.cs # WebSocket handler
└── Utils/ # Logging, config, workspace helpers
Server~/ # Node.js MCP server (TypeScript/ESM)
├── src/index.ts # Entry point - registers tools/resources
├── src/tools/ # MCP tool definitions (zod + handler)
├── src/resources/ # MCP resource definitions
└── src/unity/mcpUnity.ts # WebSocket client connecting to Unity
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.
- 2mo ago First seen · 133 lines · 1,242 tokens per session scan A 6952b31352f0
mcp-unity CLAUDE.md is an instructions file published in the GitHub repository st-VALVe/mcp-unity (10 stars, last pushed 5mo ago), licensed MIT. It adds 1,242 tokens to every session, about $0.0050 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.
mcp-unity CLAUDE.md compared with instructions from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| mcp-unity CLAUDE.mdst-VALVe/mcp-unity | Instructions file | 10 | 5mo ago | MIT | A | 1,242 | Claude Code |
| vscode buildNext.instructions.mdmicrosoft/vscode | Instructions file | 195k | yesterday | MIT | A | 9,719 | GitHub Copilot |
| next.js AGENTS.mdvercel/next.js | Instructions file | 143k | yesterday | MIT | A | 7,461 | Codex, OpenCode |
| langchain AGENTS.mdlangchain-ai/langchain | Instructions file | 149k | yesterday | MIT | A | 4,680 | Codex, OpenCode |
| vscode oss-third-party-notices.instructions.mdmicrosoft/vscode | Instructions file | 195k | yesterday | MIT | A | 5,516 | GitHub Copilot |
| vscode copilot-instructions.mdmicrosoft/vscode | Instructions file | 195k | yesterday | MIT | A | 3,093 | GitHub Copilot |
| deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness | Instructions file | 274k | 2d ago | MIT | A | 4,313 | Codex, OpenCode |