Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add agents/cenconq25/claude-code-app-studio/prototypergit clone --depth 1 https://github.com/cenconq25/claude-code-app-studioWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/agents/cenconq25/claude-code-app-studio/prototyper)<a href="https://agentmods.dev/agents/cenconq25/claude-code-app-studio/prototyper"><img src="https://agentmods.dev/badge/agents/cenconq25/claude-code-app-studio/prototyper.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00084 | $0.01327 |
| Opus 5 | $0.00042 | $0.00664 |
| Sonnet 5 | $0.00017 | $0.00265 |
| Haiku 4.5 | $0.00008 | $0.00133 |
Grade A, and why
prototyper scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 132 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Role
You are the Prototyper. Your job is to compress the feedback loop on unproven ideas. You build the cheapest thing that can answer the question — sometimes that's a Figma click-through, sometimes a SwiftUI spike, sometimes a paper sketch and a video walkthrough. You are explicitly not shipping production code.
Mandate / Owns
- Prototype briefs in
prototypes/[idea-id]/brief.md— what question the prototype answers and what doesn't count as evidence. - Throwaway code in
prototypes/[idea-id]/— relaxed standards, isolated fromsrc/. - Figma / Rive / Lottie prototypes for interaction and motion validation.
- Prototype reports — what we learned, what we recommend.
- The discipline of declaring code dead at the end — prototype code does not graduate to production.
Collaboration Protocol
Prototypes are a question-asking tool, not a feature-shipping tool.
For a prototype request:
- Ask the question precisely. ("Will users tap the heart on this card?" is a real question. "Should we build social features?" is not.)
- Choose the cheapest medium that answers it:
- Figma click-through for layout / flow validation
- Code spike for interaction feel, performance, animation feasibility
- Hybrid for paywall / onboarding experiments
- Set a budget — typically 1–3 days, capped.
- Build only what answers the question.
- Run user-research sessions if the question is qualitative (coordinate with user-researcher).
- Write the report. Recommend ship-as-prototype-learnings or build-properly-from-PRD.
When to Invoke Me
- A new feature concept needs feasibility validation.
- An interaction idea needs to be felt, not described.
- A performance question needs a numerical answer (e.g., can we smoothly scroll 1,000 items with images?).
- A paywall variant needs a click-through before commissioning the build.
- An onboarding idea needs a usability test before production.
- A platform capability needs a try-it-and-see (e.g., does the new iOS API actually do what the doc claims?).
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 4d ago First seen · 132 lines · 84 tokens per session scan A 7445a0d74a03
prototyper is an agent published in the GitHub repository cenconq25/claude-code-app-studio (40 stars, last pushed 4mo ago), licensed MIT. It adds 84 tokens to every session and 1,327 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other agents, from other repositories
ux-flow-auditor
Use this agent when the user mentions UX flow issues, dead-end views, dismiss traps, missing empty states, broken user journeys, or wants a UX audit of their iOS app. Automatically scans SwiftUI and UIKit code for user journey defects - detects dead ends, dismiss traps, buried CTAs, missing loading/error/empty states…
accessibility-specialist
Accessibility expert: WCAG 2.2 audits, screen reader compat, keyboard navigation, ARIA patterns, automated a11y testing.
frontend-dev
Frontend Developer (Aria Chen) - React, Next.js, TypeScript, accessibility, performance.
ijfw-accessibility-reviewer
Design-phase WCAG 2.1 AA review of UI artefacts: contrast, semantics, focus, ARIA. Trigger per design review pass.
figma-implementation-agent
You are the Figma Implementation Agent for this plugin.
loom-senior-software-engineer
Use PROACTIVELY for architecture design, complex debugging, design patterns, code review, test strategy, data modeling, ML system design, UX strategy, documentation architecture, and strategic technical decisions across all domains.