What is frontend-engineer?

A role and procedure for building user-interface work with React, a web interface library, and TypeScript, a language that adds type checks to JavaScript. It covers components, pages, API connections, and styling.

Use it to create UI components or pages, connect pages to APIs, apply styles, and document the completed frontend work.

It keeps frontend changes within the project’s patterns and adds a defined lint check and implementation report.

How systemowiec/ai-agents-workspace-starter configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to systemowiec/ai-agents-workspace-starter. 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/systemowiec/ai-agents-workspace-starter/main/.claude/agents/frontend-engineer.md

Clone the repo

git clone --depth 1 https://github.com/systemowiec/ai-agents-workspace-starter

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.

README.md

[![agentmods](https://agentmods.dev/badge/agents/systemowiec/ai-agents-workspace-starter/frontend-engineer/github.svg)](https://agentmods.dev/agents/systemowiec/ai-agents-workspace-starter/frontend-engineer)

Your own site

<a href="https://agentmods.dev/agents/systemowiec/ai-agents-workspace-starter/frontend-engineer"><img src="https://agentmods.dev/badge/agents/systemowiec/ai-agents-workspace-starter/frontend-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.

Your own site · 80×15

<a href="https://agentmods.dev/agents/systemowiec/ai-agents-workspace-starter/frontend-engineer"><img src="https://agentmods.dev/badge/agents/systemowiec/ai-agents-workspace-starter/frontend-engineer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 29 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.

When invoked 187 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.

Model	Per session	Once invoked
Fable 5.1	$0.00029	$0.00187
Opus 5.5	$0.00012	$0.00075
Sonnet 5.5	$0.00006	$0.00037
Haiku 4.5	$0.00003	$0.00019

Measured 2mo ago against content hash 5ebdc76059de, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

frontend-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 2mo 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-engineer.md · 22 lines

What it actually says

Read and apply strictly:

.agents/roles/frontend-engineer.md - full role definition
.agents/skills/frontend-patterns/SKILL.md - React/TS code patterns
.agents/skills/add-frontend-page/SKILL.md - new page procedure
AGENTS.md - project global rules
.agents/learnings/gotchas.md - known gotchas

When finished

Run: make lint (if available)
Save report in docs/specs/{layer}/{PREFIX}-NNN/impl-frontend-engineer.md

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.

2mo ago First seen · 22 lines · 29 tokens per session scan A 5ebdc76059de

Subscribe to this mod's changes

frontend-engineer is an agent published in the GitHub repository systemowiec/ai-agents-workspace-starter (2 stars, last pushed 7mo ago), licensed MIT. It adds 29 tokens to every session and 187 once invoked, about $0.0001 per session on Opus 5.5. 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 2026-08-31.

Frontend Languages React TypeScript

frontend-engineer next to 6 agents from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
frontend-engineersystemowiec/ai-agents-workspace-starter	Agent	2	7mo ago	MIT	A	29	Claude Code
Expert React Frontend Engineergithub/awesome-copilot	Agent	41k	yesterday	MIT	B	30	Claude Code
Frontend Developermicrosoft/skills	Agent	3.2k	yesterday	MIT	A	24	Claude Code
customchihebnabil/lovable-boilerplate	Agent	66	2d ago	MIT	A	38	GitHub Copilot
react-frontend-development-expertgiuseppe-trisciuoglio/developer-kit	Agent	367	1mo ago	MIT	A	78	Claude Code
frontend-engineerjpoley/flowspec	Agent	50	28d ago	Apache-2.0	A	24	Claude Code
migration-specialistPMDevSolutions/Aurelius	Agent	9	yesterday	MIT	A	50	Claude Code

ai-agents-workspace-starter: Agent for Claude Code