rubber-duck-review

Skills

A collection of skills for AI coding agents. Skills are packaged instructions and resources that extend agent capabilities.

About This Repository

This repo keeps the collection-style catalog and install flow from vercel-labs/agent-skills, while also keeping each skill folder plugin-ready so MCP servers, hooks, or app integrations can be added later without changing the layout. The root .claude-plugin/marketplace.json is there for future marketplace-style installs, but the main experience stays centered on npx skills add ....

Compatibility

The repo is designed around a shared skill core plus optional agent-specific plugin metadata.

Capability	Claude Code	Codex	GitHub Copilot
Install with npx skills add Vivswan/skills	Yes	Yes	Yes
Plain SKILL.md workflow	Yes	Yes	Yes
Root .claude-plugin/marketplace.json	Yes, optional enhancement	Not primary path	Not primary path
Per-skill .codex-plugin/plugin.json	Not primary path	Yes, optional enhancement	Not primary path
MCP via per-skill config	Yes, if the plugin host supports it	Yes, if the plugin host supports it	Keep a skill-only fallback

Compatibility rules for every skill in this repo:

• npx skills add ... is the primary install path across agents.
• SKILL.md must contain a complete fallback workflow even if plugin or MCP integrations are added.
• Plugin manifests are additive enhancements, not a requirement for using the skill.
• GitHub Copilot compatibility should assume skill-first installation rather than plugin-specific behavior.

Available Skills

rubber-duck-review

Cross-model code review using a second agent, tool, or read-only CLI fallback.

Use when:

• You want a second opinion before merging or shipping
• You want another model to review correctness, naming, or long-term design risk
• You want a review-only pass that will not modify files

Categories covered:

• Correctness issues
• Future-proofing risks
• Naming and design traps
• Hardcoded assumptions that may age badly

Installation

npx skills add Vivswan/skills -g

Install a specific skill:

npx skills add Vivswan/skills -g --skill rubber-duck-review

Install to a specific agent:

npx skills add Vivswan/skills -g --skill rubber-duck-review -a codex
npx skills add Vivswan/skills -g --skill rubber-duck-review -a claude-code
npx skills add Vivswan/skills -g --skill rubber-duck-review -a github-copilot

Install directly from the skill folder:

npx skills add https://github.com/Vivswan/skills/tree/main/skills/rubber-duck-review -g

Usage

Skills are automatically available once installed. The agent will use them when relevant tasks are detected.

Examples:

Rubber duck this patch before we merge it

Get a second opinion on this refactor

Creating a Basic Skill

Start from the files in template/, then add the new skill under skills/.

The full authoring guide lives in docs/authoring.md.

At minimum, a new skill should include:

• SKILL.md
• README.md
• .codex-plugin/plugin.json

If the skill needs MCP later, add a local .mcp.json based on the template example and keep the plain-skill fallback in SKILL.md.

Skill Structure

Each skill can contain:

• SKILL.md
• README.md
• .codex-plugin/plugin.json
• .mcp.json
• references/
• scripts/

Validation

Run the local validator before publishing changes:

uv run python scripts/validate-skills.py

The same checks also run in GitHub Actions through .github/workflows/validate-skills.yml.

License

MIT