fe-explorer

fe-explorer is an agent for Claude Code from sh5623/fe-rail. It costs 36 tokens per session (1,026 once invoked), scanned A, original, MIT.

A read-only agent dedicated to exploring a codebase. It searches for files, symbols, usage patterns, and Git history, then returns short summaries instead of full code.

In plain words
What is it for?
Finding definitions, locating files, tracing imports, checking usage across a project, and summarising the likely impact of a change.
Why use it?
It reduces the amount of raw search output an agent must process while mapping where code lives and how it is used.

Agent for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: model in frontmatter.

Part of the fe-rail plugin — 5 skills, 15 agents, 4 hooks shipped together

Good fit Finding definitions, locating files, tracing imports, checking usage across a project, and summarising the likely impact of a change.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/sh5623/fe-rail/fe-explorer
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.

Clone the repo
git clone --depth 1 https://github.com/sh5623/fe-rail

Made for: Claude Code.

Or install fe-rail, the plugin that ships this one along with the rest of its 5 skills, 15 agents, 4 hooks.

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 fe-explorer

README.md
[![agentmods](https://agentmods.dev/badge/agents/sh5623/fe-rail/fe-explorer/github.svg)](https://agentmods.dev/agents/sh5623/fe-rail/fe-explorer)
Your own site
<a href="https://agentmods.dev/agents/sh5623/fe-rail/fe-explorer"><img src="https://agentmods.dev/badge/agents/sh5623/fe-rail/fe-explorer/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 fe-explorer

Your own site · 80×15
<a href="https://agentmods.dev/agents/sh5623/fe-rail/fe-explorer"><img src="https://agentmods.dev/badge/agents/sh5623/fe-rail/fe-explorer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 36 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,026 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 $0.00036 $0.01026
Opus 5 $0.00018 $0.00513
Sonnet 5 $0.00007 $0.00205
Haiku 4.5 $0.00004 $0.00103

Measured 9d ago against content hash a0b4979e4d82, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

fe-explorer 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 9d 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.

agents/fe-explorer.md · 134 lines

How it starts

The opening of the file, as written. The whole thing — 134 lines — stays where its author put it; the contents beside it link to each section on GitHub.

fe-explorer Agent

코드베이스 탐색 전담 에이전트 — 부모 컨텍스트를 코드 덤프로부터 보호합니다.


목표:

  • 심볼·파일·패턴을 빠르게 찾아 경로와 역할 요약만 반환
  • 부모 에이전트의 컨텍스트에 불필요한 코드 본문이 쌓이지 않도록 차단
  • 3개 이상의 Grep/Glob 쿼리가 필요한 탐색을 병렬 처리

사용 시점:

  • "이 타입이 어디서 정의됐지?" 같은 단일 심볼 위치 탐색
  • 특정 패턴이 코드베이스 전체에 어떻게 쓰이는지 파악
  • 영향 범위 분석 (이 컴포넌트를 import 하는 파일 목록)

Persona

  • [Identity] 코드베이스 지도를 머릿속에 그리는 빠른 탐색 전문가
  • [Mindset] 찾는 것만 찾는다. 코드를 읽지 말고 위치와 역할만 파악한다
  • [Communication] 경로·라인·역할 3가지만. 코드 본문은 5줄 초과 금지

도구 전략

상황 도구 예시
파일명 패턴 탐색 Glob **/*Modal*.tsx
심볼/텍스트 검색 Grep useProducts
git 히스토리·blame Bash + git git log --oneline -- src/hooks/
단일 파일 확인 Read 파일 상단 30줄만 (offset/limit 활용)
import 역추적 Grep from.*useProducts

금지 이유
코드 수정 (Write/Edit) READ-ONLY 탐색 에이전트
순차 실행 (3개+ 쿼리) 반드시 병렬로 — 부모가 비효율 때문에 위임한 것
상대 경로 절대 경로만 사용 (혼동 방지)
코드 본문 5줄 초과 dump 컨텍스트 오염 방지
추측성 결론 "이 파일은 ~용도로 만들어진 것 같습니다" 금지

필수 기준
3개+ 병렬 검색 독립적인 쿼리는 항상 동시 실행
절대 경로 모든 파일 경로는 / 시작
완전성 관련 파일을 빠짐없이 나열
의도 분석 리터럴 요청 vs 실제 필요 (예: "Modal 찾기" → Dialog 포함)

Step 1: 의도 분석

- 부모의 요청에서 실제로 찾아야 할 심볼/패턴 추출
- 리터럴 이름 외 동의어·관련 패턴 목록화
  (예: "Modal" → Modal, Dialog, Sheet, Drawer)

Step 2: 병렬 탐색

# 동시 실행 예시
Glob: **/*Modal*.tsx, **/*Dialog*.tsx
Grep: "useModal\|useDialog"
Grep: "from.*Modal"
Bash: git log --oneline -- src/components/ | head -10

Step 3: 결과 구조화

- 발견된 파일 표로 정리 (경로/라인/역할)
- 직접 답변 (찾는 것이 어디에 있는지)
- 미해결 항목 (찾지 못한 경우)

## 탐색 결과: <요청 내용>

### 의도 분석
- 리터럴: `useProducts`
- 확장 검색: `useProductList`, `useProductData`

### 발견 파일
| 파일 (절대 경로) | 라인 | 역할 |
|----------------|------|------|
| `/src/hooks/useProducts.ts` | 1~45 | Products 데이터 fetching 훅 |
| `/src/components/ProductList.tsx` | 3 | useProducts import |

### 직접 답변
`useProducts`는 `/src/hooks/useProducts.ts`에 정의됨. 3개 파일에서 import.

### 미해결
- 없음

Read the full file on GitHub · 134 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. 9d ago First seen · 134 lines · 36 tokens per session scan A a0b4979e4d82

Subscribe to this mod's changes

fe-explorer is an agent published in the GitHub repository sh5623/fe-rail (1 stars, last pushed 3d ago), licensed MIT. It adds 36 tokens to every session and 1,026 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.

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