prototype

Builds rough runnable prototypes from ideas and converts converged ones into specced features.

150|10|Updated Feb 16, 2026
One-click install
npx skills add https://github.com/swingerman/engineer --skill prototype-swingerman
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: prototype
Source: https://github.com/swingerman/engineer/tree/main/engineer/skills/prototype
Command: npx skills add https://github.com/swingerman/engineer --skill prototype-swingerman

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve? When an idea is too vague for a written spec, this Skill builds a quick throwaway working version so you can see and feel the concept before committing to a full engineering pipeline. ## Core Features & Use Cases - Rapid Prototyping: Builds a minimal runnable artifact with hardcoded data and no tests, landing it in a gitignored prototypes/ directory. - Iteration Loop: Supports unlimited zero-ceremony rebuild rounds until the concept converges, tracked in PROTOTYPE.md and a prototypes log. - Convert to Spec: Promotes a converged prototype into the feature pipeline by seeding feature intake, reverse-engineering acceptance criteria from the artifact, and setting a size-based disposition (in-place vs rebuild). - Use Case: You have an idea for a dashboard widget but cannot describe its behavior in words. Run the prototype command, get a runnable rough cut in minutes, iterate twice, then promote it into a fully specced feature. ## Quick Start Ask the agent to prototype your idea, for example by saying "prototype a quick version of the export dialog so I can see how it feels".

Frequently Asked Questions about prototype

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I prototype an idea before writing a spec?▼

Invoke the prototype command with your idea, and it builds a minimal runnable version in a gitignored prototypes directory. You frame one thing it must demonstrate, then iterate in zero-ceremony rounds until the concept converges.

When should I use prototyping instead of writing acceptance criteria first?▼

Use prototyping when the core question is what the thing would look like or do, and a paragraph of spec cannot answer it but ten minutes of code can. Spec-first fits ideas you can already describe precisely.

What happens to a prototype after it converges?▼

A converged prototype is promoted into the feature pipeline: it is copied into a tracked feature directory, acceptance criteria are reverse-engineered from it, and a size-based disposition decides whether its code is refined in place or rebuilt.

Does the prototype need tests or production-quality code?▼

No. Prototypes deliberately skip tests, error handling, and abstractions; hardcoding and fake data are expected. The only requirement is that the artifact stays runnable so it can serve as a reference bar.

Where are prototypes stored and are they committed to git?▼

Prototypes live in a prototypes/<slug>/ directory that is added to .gitignore, making them throwaway by default. Only when promoted is the prototype copied into a tracked feature directory.