Build a throwaway prototype to answer a design question. Use when the user wants to sanity-check whether a state model or logic feels right, or explore what a UI should look like.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Prototype
A prototype is **throwaway code that answers a question**. The question decides the shape.
## Pick a branch
Identify which question is being answered, using the user's prompt, the surrounding code, or by asking if the user is around:
- **"Does this logic / state model feel right?"** → [LOGIC.md](LOGIC.md). Build a single shareable HTML file (free-play buttons plus tabbed guided walkthroughs) that pushes the state machine through cases that are hard to reason about on paper, and that a non-developer can drive.
- **"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, so 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.
## Rules that apply to both
…
The line at the top of this page pins the label git:20261007.9964061, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
GET https://markdownregistry.com/api/v1/artifacts/art_ugfk7yvsfszpvpzh
GET https://markdownregistry.com/api/v1/resolve?ref=devantler-tech/agent-plugins/prototype
GET https://markdownregistry.com/api/v1/blob/a167c4eaab6bd2e248314f57b287d90daf4d4c40311ae33a85e8c3dfe2b29ac0
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
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asymmetric-al/core · .agents/skills/prototype/SKILL.md · Build a throwaway prototype to answer a design question. Use when the user wants to sanity-check whether a state model…
