unity-coding-skills

A Claude Code plugin providing skills and agents for developing Unity projects — maintainable test design and implementation, test-first workflow, coding guidelines, scene editing, and more.

Included Skills

Included Agents

Installation

User-scope installation

Add the marketplace and install the plugin:

/plugin marketplace add nowsprinting/unity-coding-skills
/plugin install unity-coding-skills@nowsprinting-unity-coding-skills

Project-scope installation (team sharing)

Add the marketplace and install the plugin with --scope project:

/plugin marketplace add nowsprinting/unity-coding-skills
/plugin install unity-coding-skills@nowsprinting-unity-coding-skills --scope project

Commit the resulting .claude/settings.json to your repository.

[!NOTE]
When team members trust the project folder, Claude Code prompts them to install the marketplace and plugin automatically.

Recommended Project Settings

1. MCP Server Configuration

The run-tests and edit-scene skills require JetBrains built-in MCP server and extension.

1. Enable JetBrains built-in MCP server
2. Install MCP Server Extension for Unity
3. Add the following to your project .mcp.json or user MCP settings:

{
  "mcpServers": {
    "jetbrains": {
      "type": "http",
      "url": "http://localhost:64342/stream"
    }
  }
}

[!IMPORTANT]
Do not change the MCP server name jetbrains.

[!TIP]
The JetBrains MCP server also provides tools useful for Coding Agents, such as search_symbol and search_in_files_by_regex.

2. Enforcing coding rules via .editorconfig

Any coding rules or Roslyn analyzer diagnostics you want Claude to respect should be set to warning or higher severity in .editorconfig.

For example, to prevent leaving unused code, add the following diagnostics:

resharper_unused_type_local_highlighting = warning
resharper_unused_type_global_highlighting = warning
resharper_unused_member_global_highlighting = warning
resharper_unused_member_local_highlighting = warning

The Rider plugin for measuring complexity is also useful. e.g., CognitiveComplexity, CyclomaticComplexity

Usage

Test-first feature implementation planning

Type in plan mode:

/plan-feature <SPEC>

The created plan file includes the following:

• Layered-designed test cases
  • Reduce redundant tests, tests without assertions, and unnecessary test doubles
  • Editor tests
  • Unit tests (Play Mode tests)
  • Integrated tests including UI operation
  • Visual verification tests using image analysis
• Test-first development workflow
  • Effective (failable) test code
  • Definition of Done

Bug fixes through reproduction testing

Type out of plan mode:

/fix-bug <INCIDENT>

First, create, run, and verify a test that reproduces the bug, and then fix the bug.

Refine existing test code for conformance to the test design and writing guides

Type in plan mode:

/refine-tests <PATH>

Contributing

Contributions are welcome. However, we will decline contributions that we cannot maintain — such as adding support for different coding agents or MCP servers. Please fork this repository and customize it for your needs instead.

License

This project is released into the public domain under the Unlicense.