csharp-async-patterns

C# Plugin Marketplace Example

An example VS Code Agent Plugin Marketplace — a Git repository that distributes AI agent plugins for C# developers. This demonstrates all plugin component types: skills, agents, hooks, and MCP servers.

Plugins

Plugin	Description	Components
csharp-code-standards	C# naming conventions, SOLID principles, anti-pattern detection	Skill, Agent
xunit-test-generator	xUnit test scaffolding with auto-run after edits	Skill, Hook
efcore-assistant	EF Core migrations, DbContext patterns, query optimization	Skill, Agent
nuget-scout	NuGet package search, evaluation, and vulnerability checking	Skill, MCP Server
csharp-async-patterns	Async/await best practices, deadlock avoidance, CancellationToken propagation	Skill

Quick Start

1. Add this marketplace to VS Code

Add to your settings.json:

{
  "chat.plugins.marketplaces": [
    "hlotyaks/plugin-marketplace-example"
  ]
}

2. Install plugins

From Copilot Chat customizations:

• Open a Copilot Chat panel
• Click the gear icon (⚙️) to open Customizations
• Select the Plugins tab to browse available plugins from configured marketplaces
• Toggle on the plugins you want to enable

From the Command Palette:

• Run Chat: Manage Agent Plugins (Ctrl+Shift+P)
• Browse and install plugins from your configured marketplaces

From the Extensions view:

• Open Extensions (Ctrl+Shift+X)
• Search @agentPlugins to browse available plugins
• Click Install on the plugins you want

Local Development

To test plugins locally before publishing, point VS Code at your local clone:

{
  "chat.pluginLocations": {
    "C:/path/to/plugin-marketplace-example": true
  }
}

Repository Structure

.github/plugin/marketplace.json    # Plugin registry (required)
.claude-plugin/marketplace.json    # Alternate registry path
plugins/
├── csharp-code-standards/
│   ├── skills/coding-guidelines/  # Skill: naming conventions & SOLID
│   ├── agents/                    # Agent: code reviewer persona
│   └── README.md
├── xunit-test-generator/
│   ├── skills/test-generator/     # Skill: xUnit test generation
│   ├── hooks/                     # Hook: auto-run tests after edits
│   ├── scripts/                   # Shell scripts for hooks
│   └── README.md
├── efcore-assistant/
│   ├── skills/efcore-patterns/    # Skill: EF Core best practices
│   ├── agents/                    # Agent: EF Core advisor persona
│   └── README.md
├── nuget-scout/
│   ├── skills/package-search/     # Skill: package evaluation
│   ├── .mcp.json                  # MCP server: NuGet search
│   └── README.md
└── csharp-async-patterns/
    ├── skills/async-patterns/     # Skill: async/await patterns
    └── README.md

Component Types Demonstrated

• Skills (SKILL.md): Self-contained instructions the AI agent follows when the skill is relevant. All 5 plugins include skills.
• Agents (.agent.md): Custom agent personas with specific tools and focus areas. See the Code Reviewer and EF Core Advisor.
• Hooks (hooks.json): Shell commands that run at agent lifecycle points. The xUnit plugin auto-runs tests after file edits.
• MCP Servers (.mcp.json): External tool integrations via the Model Context Protocol. The NuGet Scout plugin demonstrates this pattern.

Learn More

• Custom Plugin Marketplace Guide — Detailed guide included in this repo
• Agent Plugins Documentation
• MCP Servers Documentation

License

MIT