game-mcp copilot-instructions.md

game-mcp copilot-instructions.md is an instructions file for GitHub Copilot from moonolgerd/game-mcp. It costs 989 tokens per session, scanned A, original, MIT.

Project-specific instructions for a C# Model Context Protocol server that discovers installed games on Windows. They describe its single-file design, tool registration, and platform-specific discovery patterns.

In plain words
What is it for?
Use them when adding or modifying game-platform discovery, MCP tools, JSON serialization, error handling, or mappings in `game-mcp.cs`.
Why use it?
They give an AI coding assistant the conventions needed to change this game-discovery server without breaking its architecture or behavior.

Instructions file for GitHub Copilot

Install

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.

agentmods
npx agentmods add instructions/moonolgerd/game-mcp/copilot-instructions
Clone the repo
git clone --depth 1 https://github.com/moonolgerd/game-mcp

Made for: GitHub Copilot.

Wrote 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.

agentmods badge for game-mcp copilot-instructions.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/moonolgerd/game-mcp/copilot-instructions.svg)](https://agentmods.dev/instructions/moonolgerd/game-mcp/copilot-instructions)
Your own site
<a href="https://agentmods.dev/instructions/moonolgerd/game-mcp/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/moonolgerd/game-mcp/copilot-instructions.svg" alt="Measured on agentmods" height="20"></a>
Per session 989 This file is loaded in full into every session.
When invoked 989 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00989 $0.00989
Opus 5 $0.00495 $0.00495
Sonnet 5 $0.00198 $0.00198
Haiku 4.5 $0.00099 $0.00099

Measured 4d ago against content hash 2cc461aa153c, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

game-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 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.

.github/copilot-instructions.md · 102 lines

How it starts

The opening of the file, as written. The whole thing — 102 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Game Discovery MCP Server - AI Agent Instructions

Architecture Overview

This is a Model Context Protocol (MCP) server built as a single C# script (game-mcp.cs) that discovers installed games across multiple Windows platforms. The project uses:

  • Single-file architecture: Everything in game-mcp.cs (683 lines) - no traditional project structure
  • Top-level program: Uses C# 9+ top-level statements with inline package references
  • MCP framework: Uses [email protected] with .NET hosting
  • JSON source generation: Uses GameJsonContext for AOT-compatible serialization

Key Patterns & Conventions

MCP Tool Registration Pattern

[McpServerToolType]
public static class GameDiscoveryTools
{
    [McpServerTool(Name = "discover_games")]
    [Description("...")]
    public static async Task<string> DiscoverGames() { ... }
}

Platform Discovery Pattern

Each platform (Steam, Epic, GOG, Xbox, Registry) follows this structure:

  • Private DiscoverXxxGames() method returning List<Game>
  • Registry/file system scanning with error isolation
  • Graceful degradation when platforms unavailable
  • Consistent Game object mapping

Error Handling Convention

  • Continue on platform errors: Individual platform failures don't break discovery
  • Stderr logging: Uses Console.Error.WriteLine() for debugging without breaking MCP protocol
  • JSON error responses: All tools return JSON with ErrorResponse type for failures

JSON Serialization Approach

  • Source generation required: Uses GameJsonContext.Default.XxxType pattern
  • Response classes: Separate DTOs (GameInfo, GameDiscoveryResult, LaunchResponse, ErrorResponse)
  • No reflection: AOT-compatible with [JsonSerializable] attributes

Critical Development Workflows

Running the MCP Server

dotnet run game-mcp.cs  # Starts stdio MCP server

VS Code Integration

Configure in .vscode/mcp.json:

{
  "servers": {
    "game-discovery": {
      "type": "stdio", 
      "command": "dotnet",
      "args": ["run", "D:\\Repos\\game-mcp\\game-mcp.cs"]
    }
  }
}

Read the full file on GitHub · 102 lines

Changes

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.

  1. 4d ago First seen · 102 lines · 989 tokens per session scan A 2cc461aa153c

Subscribe to this mod's changes

game-mcp copilot-instructions.md is an instructions file published in the GitHub repository moonolgerd/game-mcp (0 stars, last pushed 6mo ago), licensed MIT. It adds 989 tokens to every session, about $0.0049 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.