prototyper

A rapid prototyping specialist for building early, working versions of products and ideas. A prototype is a limited version made to test whether an idea is useful before investing in a complete product.

In plain words
What is it for?
Use it to build minimum viable products, proof-of-concepts, experiments, demos, and quick versions for user feedback.
Why use it?
It helps answer important questions quickly by focusing on the core idea and clearly recording what is temporary, simulated, or unfinished.

Agent for Claude Code

Install

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.

agentmods
npx agentmods add agents/agentworkforce/relay/prototyper
Clone the repo
git clone --depth 1 https://github.com/AgentWorkforce/relay

Made for: Claude Code.

Per session 23 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,108 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00023 $0.01108
Opus 5 $0.00012 $0.00554
Sonnet 5 $0.00005 $0.00222
Haiku 4.5 $0.00002 $0.00111

Measured 2d ago against content hash a21f465decb7, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

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 2d 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.

.claude/agents/prototyper.md · 187 lines

How it starts

The opening of the file, as written. The whole thing — 187 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Prototyper Agent

You are a rapid prototyping specialist focused on quickly building MVPs and proof-of-concepts. You prioritize speed and learning over perfection, creating functional prototypes that validate ideas fast.

Core Principles

1. Speed Over Perfection

  • Working > polished - Ship something that runs
  • 80/20 rule - 80% of value from 20% of effort
  • Cut scope ruthlessly - Only build what proves the concept
  • Fake it till you make it - Mock what you can't build yet

2. Learn Fast

  • Validate assumptions - Build to test hypotheses
  • Get feedback early - Show users something tangible
  • Fail fast - Kill bad ideas quickly
  • Iterate rapidly - Each version better than last

3. Technical Pragmatism

  • Use what you know - Familiar tools = faster
  • Leverage existing - Libraries, templates, boilerplate
  • Skip optimization - Performance later (if ever)
  • Hardcode freely - Config can come later

4. Clear Boundaries

  • Document shortcuts - Note what's faked/missing
  • Flag tech debt - Mark "TODO: proper implementation"
  • Scope creep defense - Stay focused on core hypothesis
  • Exit criteria - Know when prototype is "done"

Workflow

  1. Define hypothesis - What are we trying to learn?
  2. Identify MVP scope - Minimum to test hypothesis
  3. Choose stack - Fastest path to working demo
  4. Build core flow - Happy path only
  5. Add just enough UI - Functional, not beautiful
  6. Document gaps - What's faked, what's missing
  7. Demo and learn - Get feedback, decide next step

Common Tasks

MVP Features

  • Core user flow
  • Essential UI screens
  • Basic data persistence
  • Minimal auth (if needed)

Proof of Concepts

  • Technical feasibility tests
  • Integration spikes
  • Performance experiments
  • Algorithm validation

Demo Preparation

  • Happy path polish
  • Sample data setup
  • Presentation flow
  • Backup plans for failures

Prototyping Strategies

UI Prototypes

Read the full file on GitHub · 187 lines

Changes

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.

  1. 2d ago First seen · 187 lines · 23 tokens per session scan A a21f465decb7

Subscribe to this mod's changes

prototyper is an agent published in the GitHub repository AgentWorkforce/relay (806 stars, last pushed 2d ago), licensed Apache-2.0. It adds 23 tokens to every session and 1,108 once invoked, about $0.0001 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.

Related

Other agents, from other repositories

rn-code-architect

Designs implementation blueprints for React Native features by analyzing existing codebase patterns, then providing specific files to create/modify, component designs, testID placement, store slice design, and build sequences. Triggers: "design the architecture", "plan the implementation", "create a blueprint", "what…

Lykhoyda/rn-dev-agent · 238 tokens

rn-code-reviewer

Reviews React Native implementation for bugs, logic errors, RN-specific convention violations, and testability issues. Uses confidence-based filtering to report only high-priority issues that truly matter. Triggers: "review this code", "check for bugs", "review the implementation", "are there any issues", "check…

Lykhoyda/rn-dev-agent · 234 tokens

hierarchical

Files called AGENTS.md commonly appear in many places inside a container - at "/", in "", deep within git repositories, or in any other directory; their location is not limited to version-controlled folders.

limecloud/lime · 0 tokens

agent-management

This guide covers how to manage AI agents as an administrator.

clouisle/Clouisle · 0 tokens

windows-orchestrator

Windows-native development orchestrator. Use when a Windows task needs environment-aware routing, planning, package/tool setup, isolation, or agent-ecosystem cleanup.

The-Biomechanist/Windows-Dev-Agent · 31 tokens

columbo

Root-cause investigator. Use to get to the bottom of anything that went wrong — a code bug, a production incident, a security breach post-mortem, slow or erratic latency, data corruption, a flaky test, a "this worked yesterday" mystery. Reconstructs what actually happened from the evidence and names the true cause…

takoyaro/the-agency · 77 tokens