What is frontend-developer?

A specialist for building React user interfaces that adapt to different screen sizes. It covers common frontend work such as interface components, application state, speed, accessibility, and frontend structure.

Creating UI components, managing React state, improving frontend performance, adding accessibility support, and planning frontend architecture.

It helps when frontend tasks require knowledge of React, responsive layouts, accessibility, or performance instead of general coding assistance.

frontend-developer — Agent by dy9759

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/dy9759/specskillsforclaudecode/frontend-developer

Clone the repo

git clone --depth 1 https://github.com/dy9759/SpecSkillsForClaudeCode

Made for: Claude Code.

Per session 37 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.

When invoked 258 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. Scan, not verified.

Origin unknown 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	$0.00037	$0.00258
Opus 5	$0.00018	$0.00129
Sonnet 5	$0.00007	$0.00052
Haiku 4.5	$0.00004	$0.00026

Measured 2d ago against content hash 7247ea7bda89, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

frontend-developer 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/frontend-developer.md · 33 lines

The source is not reproduced here

No licence file

Read it on GitHub

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.

2d ago First seen · 33 lines · 37 tokens per session scan A 7247ea7bda89

Subscribe to this mod's changes

frontend-developer is an agent published in the GitHub repository dy9759/SpecSkillsForClaudeCode (5 stars, last pushed 9mo ago), with no licence file. It adds 37 tokens to every session and 258 once invoked, about $0.0002 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 2026-08-31.

Frontend React

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frontend-developer