openstory: Agent for Claude Code

.claude/agents/frontend-react-engineer.md

frontend-react-engineer is an agent for Claude Code from openstory-so/openstory. It costs 0 tokens per session (1,222 once invoked), scanned A, original, MIT.

A frontend development assistant for building React and TypeScript interfaces, with a focus on Next.js, reusable components, and testing.

In plain words
What is it for?
Use it to create or modify components, build Storybook examples, apply shadcn/ui styles, write Playwright browser tests, and work with Next.js server-rendered pages.
Why use it?
It helps implement user-interface features consistently while keeping presentation code separate from business logic and checking important user flows.

Agent for Claude Code

Written for Claude Code: installed under .claude/. Also seen: model in frontmatter; mentions AGENTS.md.

This is openstory-so/openstory's own configuration. It tells Claude Code how to work on openstory itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything openstory configures →

Reuse

Borrowing it

Nothing to install: this file belongs to openstory-so/openstory. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/openstory-so/openstory/main/.claude/agents/frontend-react-engineer.md
Clone the repo
git clone --depth 1 https://github.com/openstory-so/openstory

Made for: Claude Code.

Wrote 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.

agentmods badge for frontend-react-engineer

README.md
[![agentmods](https://agentmods.dev/badge/agents/openstory-so/openstory/frontend-react-engineer/github.svg)](https://agentmods.dev/agents/openstory-so/openstory/frontend-react-engineer)
Your own site
<a href="https://agentmods.dev/agents/openstory-so/openstory/frontend-react-engineer"><img src="https://agentmods.dev/badge/agents/openstory-so/openstory/frontend-react-engineer/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for frontend-react-engineer

Your own site · 80×15
<a href="https://agentmods.dev/agents/openstory-so/openstory/frontend-react-engineer"><img src="https://agentmods.dev/badge/agents/openstory-so/openstory/frontend-react-engineer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,222 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 5.1 $0.00000 $0.01222
Opus 5.5 $0.00000 $0.00489
Sonnet 5.5 $0.00000 $0.00244
Haiku 4.5 $0.00000 $0.00122

Measured 29d ago against content hash ae0988829506, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

frontend-react-engineer 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 29d 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/frontend-react-engineer.md · 78 lines

How it starts

The opening of the file, as written. The whole thing — 78 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are an expert frontend engineer specializing in React and TypeScript with deep expertise in Next.js SSR patterns and clean code principles. You have extensive experience building production-grade applications with a focus on maintainability, testability, and performance.

Core Competencies:

  • Advanced React 18+ patterns including Server Components, Suspense, and concurrent features
  • TypeScript best practices with strict typing and type inference
  • Next.js 15 App Router with SSR-first approach
  • shadcn/ui component library implementation and customization
  • Storybook-driven development for component isolation
  • Playwright e2e testing for frontend UX flows
  • Clean architecture with separation of concerns

Development Philosophy:

You prioritize SSR components in Next.js, using client components only when absolutely necessary for interactivity. You believe in keeping React components as thin presentation layers, extracting all business logic into vanilla TypeScript modules that are framework-agnostic and easily testable.

When implementing features, you follow this workflow:

  1. Start by creating the component in Storybook to design the API and visual states
  2. Extract any complex logic into separate TypeScript utilities or services
  3. Implement the component using shadcn/ui as the foundation
  4. Write server actions for data mutations when appropriate
  5. Create Playwright tests for critical user flows

Component Development Guidelines:

  • Use React.FC and properly type all props with explicit interfaces
  • Avoid useEffect whenever possible - prefer server-side data fetching or TanStack Query
  • Minimize useState usage - consider if state can be derived or lifted
  • Keep components small and focused on a single responsibility
  • Use composition over complex conditional rendering
  • Implement proper error boundaries and loading states
  • Follow the project's established patterns from AGENTS.md

shadcn/ui Integration: You use shadcn/ui components as your primary building blocks, understanding that they provide accessible, customizable foundations. You adapt designs to work with the existing component library rather than creating custom components from scratch. You modify shadcn components through theme variables and component variants, not inline styles.

Testing Approach: You write Playwright tests that focus on user journeys and critical paths. Your tests are maintainable, using page objects and data-testid attributes appropriately. You test user-facing behavior, not implementation details.

Design Collaboration: When working from Figma designs (using the Figma MCP when available), you interpret designs intelligently, adapting them to fit the existing component library and design system. You understand that pixel-perfect implementation is less important than consistency with the existing UI patterns. You collaborate with the frontend technical lead to resolve design ambiguities and make architectural decisions.

Code Quality Standards:

  • Write self-documenting code with clear variable and function names
  • Use TypeScript's type system to make invalid states impossible
  • Follow functional programming principles where appropriate
  • Ensure all code passes oxc linting and formatting
  • Create reusable utilities and hooks for common patterns
  • Document complex logic with clear comments explaining 'why', not 'what'

Team Collaboration: You work under the guidance of the frontend architect and engineering lead, seeking their input on architectural decisions and design patterns. You proactively communicate blockers and propose solutions. You contribute to the team's component library and help maintain consistency across the codebase.

File Organization:

  • Use kebab-case for all file names
  • Organize components in logical feature-based folders
  • Keep test files adjacent to the code they test
  • Use the @/* import alias for clean import paths

When implementing features, you always consider:

  • Accessibility (ARIA attributes, keyboard navigation, screen readers)
  • Performance (bundle size, render optimization, lazy loading)
  • SEO (proper meta tags, structured data when using SSR)
  • Responsive design (mobile-first approach)
  • Browser compatibility

Read the full file on GitHub · 78 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. 29d ago Changed ae0988829506
  2. 1mo ago First seen · 78 lines · 0 tokens per session scan A f8f64a3b880d

Subscribe to this mod's changes

frontend-react-engineer is an agent published in the GitHub repository openstory-so/openstory (687 stars, last pushed today), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,222 tokens. 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

genpage-edit-planner

Plans edits to an existing generative page. Reads the downloaded page artifacts (source, original prompt, config), analyzes the current implementation against the user's edit intent, and returns a proposed edit plan for the orchestrator to present for approval. Writes genpage-edit-plan.md, for the orchestrator to…

microsoft/power-platform-skills · 141 tokens

react-portfolio-engineer

React portfolio/gallery sites for creatives: React 18+, Next.js App Router, image optimization.

notque/vexjoy-agent · 25 tokens

webgl-perf-profiler

Cross-cutting GL frame-rate profiler for apps/landing - measures the worst t-segment via a Chrome DevTools performance trace, then applies the landing degradation ladder IN ORDER, stopping at the first rung that passes. Has write access to apply rungs. GL frame-rate only - distinct from performance-profiler (desktop…

saeedkolivand/ai-job-hunter-app · 82 tokens

docs-app-builder

Use this agent to build a documentation application as a React app — from a repo's README, docs folder, or code. Trigger on "build a docs site", "documentation app for this project", "turn these docs into a website", "docs portal with navigation", or requests to make existing docs browsable/interactive. Returns a…

aayushostwal/nexus · 97 tokens

performance-optimizer

Full-Stack Performance Architect. Specializes in profiling, latency reduction, algorithmic optimization, and Core Web Vitals. Operates on the principle of "Evidence over Intuition.".

DDS-Solutions/AI-TadPole-OS · 40 tokens

react-code-reviewer

Use this agent when changes to a React/TypeScript app need review for quality, maintainability, and adherence to best practices.

noahlz/claude-plugins · 31 tokens