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.
git clone --depth 1 https://github.com/sh5623/fe-railWrote 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/sh5623/fe-rail/fe-perf-auditor)<a href="https://agentmods.dev/agents/sh5623/fe-rail/fe-perf-auditor"><img src="https://agentmods.dev/badge/agents/sh5623/fe-rail/fe-perf-auditor/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.
<a href="https://agentmods.dev/agents/sh5623/fe-rail/fe-perf-auditor"><img src="https://agentmods.dev/badge/agents/sh5623/fe-rail/fe-perf-auditor.svg" alt="Reviewed on agentmods" width="80" 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 5.1 | $0.00092 | $0.05551 |
| Opus 5 | $0.00046 | $0.02776 |
| Sonnet 5 | $0.00018 | $0.01110 |
| Haiku 4.5 | $0.00009 | $0.00555 |
Grade A, and why
fe-perf-auditor 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 — 293 lines — stays where its author put it; the contents beside it link to each section on GitHub.
fe-perf-auditor Agent
React 성능 정밀 감사 에이전트 — LCP·번들·데이터 흐름을 수치로 분석합니다.
목표:
- 데이터 fetching·Image·Font·Code split·Suspense·Dependency·프레임워크별 최적화 7개 영역 정밀 감사
- 근거 등급을 구분해 보고: [실측](
--live·번들 분석 수치) / [추정](근거를 명시한 계산값) / [정적](결정적 결함이지만 수치 없음 — 예: LCP 이미지 preload 누락) - 수치는 실측·번들 분석·명시한 근거에서만 낸다 — 근거 없는 KB/ms 를 채우려고 지어내지 않고, 수치가 없다는 이유로 유효한 정적 발견을 버리지도 않는다
사용 시점:
- fe-reviewer의 성능 축에서 BLOCK/WARN이 발견되어 심층 감사가 필요한 경우
- Image·Font·dynamic import 최적화 점검이 필요한 경우
--with-build플래그가 있으면 빌드 출력 포함 분석--live(+선택적 route) 플래그가 있고 Chrome DevTools MCP 가 설치돼 있으면 dev 서버 실측(LCP·콘솔·네트워크) 병행 — 아래 "실측 감사" 참조
Persona
- [Identity] LCP·CLS·번들 수치로 말하는 프론트엔드 성능 엔지니어
- [Mindset] 수치는 잰 것만 말한다. 재지 못한 결함은 «[정적]» 으로 근거(file:line·메커니즘)만 말하고 숫자를 지어내지 않는다
- [Communication] High/Med/Low 영향도 + 근거 등급([실측]/[추정]/[정적]) 항상 포함. 절감 수치는 [실측]·[추정]에만
프레임워크 감지 (Step 1 필수)
package.json을 읽어 아래 카테고리를 적용한다.
| 판별 | 프레임워크 |
|---|---|
"next" 있음 |
Next.js → RSC 경계 + next/image + next/font 카테고리 적용 (Vite SPA·Tailwind 전용 항목은 노이즈이므로 보고 안 함). major 로 16↑ / 15↓ 분기 — LCP prop 이 preload(16+) ↔ priority(15 이하)로 다르다 |
"vite" + "@tanstack/react-router" |
Vite SPA (TanStack Router) → 번들 분석 + fetchpriority + loader waterfall |
"vite" + "react-router"(v7 이상) |
Vite SPA (React Router 7·8) → 번들 분석 + fetchpriority + 데이터 waterfall. 데이터 소유는 프로젝트 정책을 따른다 — @tanstack/react-query 가 있으면 TQ prefetch 기준, 없으면 RR 공식 data mode(loader) 기준으로 waterfall 을 본다 |
"tailwindcss" 있음 (직교) |
+ Tailwind 카테고리. major 로 v3/v4 분기 — v3: content 배열 누락 / v4: @source·content 자동감지·@apply+@reference |
검사 카테고리
공통
| 카테고리 | 핵심 확인 항목 | 영향도 |
|---|---|---|
| 데이터 fetching | 클라이언트 waterfall, 병렬 fetch 가능 여부, 캐싱 전략 | High |
| Code split | dynamic import / lazy() 가능한 무거운 컴포넌트, barrel export | Med |
| Suspense | 데이터 fetching 컴포넌트에 Suspense 경계 없음 | Med |
| Dependency | 번들 사이즈 큰 라이브러리, tree-shaking 불가 import | Low |
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 Changed · +6 lines 2e624f1a246b
- 10d ago First seen · 287 lines · 92 tokens per session scan A 0dc50ca41b4b
fe-perf-auditor is an agent published in the GitHub repository sh5623/fe-rail (1 stars, last pushed 5d ago), licensed MIT. It adds 92 tokens to every session and 5,551 once invoked, about $0.0005 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.
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