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/ivanmurzak/unity-mcp/copilot-instructionsgit clone --depth 1 https://github.com/IvanMurzak/Unity-MCPWhat 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 | $0.00895 | $0.00895 |
| Opus 5 | $0.00447 | $0.00447 |
| Sonnet 5 | $0.00179 | $0.00179 |
| Haiku 4.5 | $0.00089 | $0.00089 |
Grade A, and why
Unity-MCP copilot-instructions.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 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 — 63 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Project Guidelines
Critical Rules
No C# Reflection for Private Access
PROHIBITED: Using System.Reflection to access private, internal, or otherwise non-public fields, properties, methods, or classes in project code. This includes Type.GetType, BindingFlags.NonPublic, GetMethod, GetField, GetProperty, and similar reflection APIs when used to bypass access modifiers.
Example of prohibited code:
// WRONG: Accessing internal Unity API via reflection
var logEntriesType = Type.GetType("UnityEditor.LogEntries, UnityEditor.CoreModule")
?? Type.GetType("UnityEditorInternal.LogEntries, UnityEditor.CoreModule")
?? Type.GetType("UnityEditor.LogEntries, UnityEditor")
?? Type.GetType("UnityEditorInternal.LogEntries, UnityEditor");
logEntriesType?.GetMethod("Clear", BindingFlags.Static | BindingFlags.Public)
?.Invoke(null, null);
Note: This rule does NOT apply to
ReflectorNetlibrary usage, which is an external dependency specifically designed for reflection-based access patterns.
Code Review
Before performing any code review, you MUST read the project constitution: .specify/memory/constitution.md. All code review feedback must verify adherence to the principles defined in the constitution. Constitution principles supersede ad-hoc practices when conflicts arise.
Code Style
- C#: Use 4 spaces indentation. PascalCase for classes/methods/properties,
_camelCasefor private readonly fields.- Namespace:
com.IvanMurzak.Unity.MCP. - Example: UnityMcpPlugin.cs.
- Namespace:
- PowerShell: Use K&R brace style.
Architecture
- Unity-MCP-Plugin: Main Unity package.
- Core logic: Packages/com.ivanmurzak.unity.mcp/Runtime.
- Editor logic:
Packages/com.ivanmurzak.unity.mcp/Editor. - Tests:
Packages/com.ivanmurzak.unity.mcp/Tests.
- MCP Server: lives in the shared GameDev-MCP-Server repo (binary
gamedev-mcp-server); the plugin downloads the release pinned byMcpServerManager.ServerVersion. - Installer: Installer/ wraps the package installation.
- Unity-Tests: Unity-Tests/ contains projects for different Unity versions (2022, 2023, 6000) linking locally to the Plugin.
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 · 63 lines · 895 tokens per session scan A 711e3a538ec1
Unity-MCP copilot-instructions.md is an instructions file published in the GitHub repository IvanMurzak/Unity-MCP (4,047 stars, last pushed 9d ago), licensed Apache-2.0. It adds 895 tokens to every session, about $0.0045 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
unity-mcp CLAUDE.md
Claude Code instructions for CoplayDev/unity-mcp, covering claude.md, what this project is, architecture, three layers on the python side and transport modes.
mcp-unity AGENTS.md
Instructions for CoderGamester/mcp-unity, covering mcp unity — ai agent guide (mcp package), purpose (what this repo is), how it works (high-level data flow), key defaults & invariants and repo layout (where to change what).
turn-based-game-mcp mcp-server.instructions.md
MCP server development patterns for the turn-based games platform.
turn-based-game-mcp shared-library.instructions.md
Shared library development patterns for the turn-based games platform.
turn-based-game-mcp typescript.instructions.md
TypeScript development patterns and best practices for the turn-based games platform.
turn-based-game-mcp api-routes.instructions.md
Next.js API route development patterns for the turn-based games platform.