prototype
Build a throwaway prototype to answer a design question before committing to real implementation. Generates either a runnable terminal app (for state machines, data models, business logic) or several radically different UI variations on one route (for visual/layout decisions). Use when the user wants to prototype, spike, POC, sanity-check a data model, mock up a UI, explore design options, or says "prototype this", "spike this out", "let me play with it", "try a few designs", "sketch this in code", "I want to try something before building it for real", "quick and dirty version", or "validate this approach" — even if they don't use the word "prototype."
What this skill does
# Prototype
A prototype is **throwaway code that answers a question**. The question decides the shape.
If the user passed arguments, treat them as the question the prototype should answer.
## Pick a branch
Identify which question is being answered — from the user's prompt, the arguments, the surrounding code, or by asking if the user is around. The litmus test: **if the user could answer the question by looking at a screen, it's UI. If they'd need to push buttons and watch state change, it's logic.**
- **"Does this logic / state model feel right?"** → [LOGIC.md](LOGIC.md). Build a tiny interactive app that pushes the state machine through cases that are hard to reason about on paper.
- **"What should this look like?"** → [UI.md](UI.md). Generate several radically different UI variations on a single route, switchable via a URL search param and a floating bottom bar.
The two branches produce very different artifacts — getting this wrong wastes the whole prototype. If the question is genuinely ambiguous and the user isn't reachable, default to whichever branch better matches the surrounding code (a backend module → logic; a page or component → UI) and state the assumption at the top of the prototype.
## Scaffolder
Before writing boilerplate, run the bundled scaffolder to generate the repetitive parts (switcher component, TUI shell, variant stubs). Then fill in the interesting parts — the actual variants or the domain logic.
```bash
# UI prototype: generates PrototypeSwitcher + variant shells
npx tsx ${CLAUDE_PLUGIN_ROOT}/skills/prototype/scripts/scaffold.ts ui --variants 3 --framework next --outdir ./src/app/settings
# Logic prototype: generates portable logic module + TUI shell
npx tsx ${CLAUDE_PLUGIN_ROOT}/skills/prototype/scripts/scaffold.ts tui --name checkout-flow --outdir ./src/checkout
```
The scaffolder handles React UI (Next, React Router, Vite) and TypeScript TUI. For other UI frameworks, it creates the directory structure with React components — adapt them to your framework.
## Rules that apply to both
1. **Throwaway from day one, and clearly marked as such.** Locate the prototype code close to where it will actually be used (next to the module or page it's prototyping for) so context is obvious. Use a naming convention that makes it impossible to confuse with production code — prefix files or folders with `__prototype-` or put them in a `prototype/` subfolder next to the target module. For throwaway UI routes, obey whatever routing convention the project already uses; don't invent a new top-level structure.
2. **One command to run.** Whatever the project's existing task runner supports — `pnpm <name>`, `python <path>`, `bun <path>`, etc. The user must be able to start it without thinking.
3. **No persistence by default.** State lives in memory. Persistence is the thing the prototype is _checking_, not something it should depend on. If the question explicitly involves a database, hit a scratch DB or a local file with a clear "PROTOTYPE — wipe me" name.
4. **Skip the polish.** No error handling beyond what makes the prototype _runnable_, no abstractions. Don't build a test suite — if a single assertion would save you from a dumb mistake while iterating, that's fine, but if you're writing more than one you've left prototype territory. The point is to learn something fast and then delete it.
5. **Surface the state.** After every action (logic) or on every variant switch (UI), print or render the full relevant state so the user can see what changed.
6. **Delete or absorb when done.** When the prototype has answered its question, either delete it or fold the validated decision into the real code — don't leave it rotting in the repo.
## When done
The _answer_ is the only thing worth keeping from a prototype. Capture it somewhere durable (commit message, ADR, issue, or a `NOTES.md` next to the prototype) along with the question it was answering. If the user is around, that capture is a quick conversation; if not, leave the placeholder so they (or you, on the next pass) can fill in the verdict before deleting the prototype.
Related in Design
contribute
IncludedLocal-only OSS contribution command center. Auto-refreshes the user's in-flight PR and issue state on invoke so conversations start with full context — no need to brief Claude on what's in flight. Helps the user find issues to contribute to on GitHub, builds per-repo dossiers of what each upstream expects (CLA, DCO, branch convention, AI policy, draft-first, review bots, issue templates), runs deterministic gates before any external action so AI-assisted contributions don't reach maintainers as slop. State is markdown-only: candidate files at ~/.contribute-system/candidates/, repo dossiers at ~/.contribute-system/research/, append-only event log at ~/.contribute-system/log.jsonl. No database, no cloud calls. Use when the user asks about their PRs / issues / contributions, wants to find new work to take on, claim an issue, build/refresh a repo's dossier, or draft a Design Issue or PR. Trigger with "/contribute", "what's my PR status", "find a contribution", "claim issue X", "draft a Design Issue for Y", "refresh dossier for Z".
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mcp
IncludedModel Context Protocol (MCP) server development and tool management. Languages: Python, TypeScript. Capabilities: build MCP servers, integrate external APIs, discover/execute MCP tools, manage multi-server configs, design agent-centric tools. Actions: create, build, integrate, discover, execute, configure MCP servers/tools. Keywords: MCP, Model Context Protocol, MCP server, MCP tool, stdio transport, SSE transport, tool discovery, resource provider, prompt template, external API integration, Gemini CLI MCP, Claude MCP, agent tools, tool execution, server config. Use when: building MCP servers, integrating external APIs as MCP tools, discovering available MCP tools, executing MCP capabilities, configuring multi-server setups, designing tools for AI agents.
react-native-skia
IncludedDesign, build, debug, and optimise high-polish animated graphics in React Native or Expo using @shopify/react-native-skia, Reanimated, and Gesture Handler. Use when the user wants canvas-driven UI, shaders, paths, rich text, image filters, sprite fields, Skottie, video frames, snapshots, web CanvasKit setup, or performance tuning for custom motion-heavy elements such as loaders, hero art, cards, charts, progress indicators, particle systems, or gesture-driven surfaces. Also use when the user asks for fluid, glow, glass, blob, parallax, 60fps/120fps, or GPU-friendly animated effects in React Native, even if they do not explicitly say "Skia". Do not use for ordinary form/layout work with standard views.
plaid
IncludedProduct Led AI Development — guides founders from idea to launched product. Six capabilities: Idea (discover a product idea), Validate (pressure-test the idea against fatal flaws, problem reality, competition, and 2-week MVP feasibility), Plan (vision intake + document generation), Design (translate image references into a design.md spec), Launch (go-to-market strategy), and Build (roadmap execution). Use when someone says "PLAID", "plaid idea", "help me find an idea", "product idea", "idea from my business", "idea from my expertise", "plaid validate", "validate my idea", "pressure-test", "is this idea good", "find fatal flaws", "validate the problem", "plan a product", "define my vision", "generate a PRD", "product strategy", "plaid design", "design from image", "translate image to design", "create design.md", "extract design tokens", "plaid launch", "go-to-market", "launch plan", "GTM strategy", "launch playbook", "plaid build", "build the app", "start building", or "execute the roadmap".
nextjs-framer-motion-animations
IncludedAdds production-safe Motion for React or Framer Motion animations to Next.js apps, including reveal, hover and tap micro-interactions, whileInView, stagger, AnimatePresence, layout and layoutId transitions, reorder, scroll-linked UI, and lightweight route-content transitions. Use when the user asks to add, refactor, or debug Motion or Framer Motion in App Router or Pages Router codebases, especially around server/client boundaries, reduced motion, LazyMotion, bundle size, hydration, or route transitions. Avoid for GSAP-style timelines, WebGL or 3D scenes, heavy scroll storytelling, or CSS-only effects unless Motion is explicitly requested.