security

security is a skill for Claude Code from sonature-lab/timsquad. It costs 36 tokens per session (1,133 once invoked), scanned A, original, MIT.

A security guide for Flutter mobile apps, covering protected storage, authentication, network connections, data encryption, and code protection. OWASP MASVS is a set of recommended mobile-app security checks.

In plain words
What is it for?
Use it to configure secure storage, biometric login, token refresh, SSL certificate pinning, build-time secrets, code obfuscation, and encrypted local databases.
Why use it?
It helps prevent tokens, API keys, local data, and network traffic from being exposed through the app or its build process.

Skill for Claude Code

Written for Claude Code: user-invocable in frontmatter.

Good fit Use it to configure secure storage, biometric login, token refresh, SSL certificate pinning, build-time secrets, code obfuscation, and encrypted local databases.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/sonature-lab/timsquad/security
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.

Any agent
npx skills add sonature-lab/timsquad --skill security
Clone the repo
git clone --depth 1 https://github.com/sonature-lab/timsquad

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 security

README.md
[![agentmods](https://agentmods.dev/badge/skills/sonature-lab/timsquad/security/github.svg)](https://agentmods.dev/skills/sonature-lab/timsquad/security)
Your own site
<a href="https://agentmods.dev/skills/sonature-lab/timsquad/security"><img src="https://agentmods.dev/badge/skills/sonature-lab/timsquad/security/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 security

Your own site · 80×15
<a href="https://agentmods.dev/skills/sonature-lab/timsquad/security"><img src="https://agentmods.dev/badge/skills/sonature-lab/timsquad/security.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 36 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,133 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 $0.01133
Opus 5.5 $0.00014 $0.00453
Sonnet 5.5 $0.00007 $0.00227
Haiku 4.5 $0.00004 $0.00113

Measured 1mo ago against content hash 49355eaf9fd4, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

security 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 1mo 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.

templates/base/skills/tsq-flutter/security/SKILL.md · 87 lines

How it starts

The opening of the file, as written. The whole thing — 87 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Security

Flutter 모바일 보안 가이드. 저장소 암호화, 전송 보안, 실행 보호, 인증 강화. OWASP MASVS 기준 L1/L2 준수를 목표로 레이어별 독립 방어.

Philosophy

  • 보안은 레이어 — 저장(암호화), 전송(TLS+pinning), 실행(난독화) 각각 독립 방어
  • 키는 코드에 없다 — 빌드 시 주입, 런타임 안전 저장소
  • 인증은 로컬 + 원격 이중 — biometric은 UX, 토큰은 보안

Resources

6개 규칙 + 1개 참조. 모바일 보안 전체 레이어를 커버.

Priority Type Resource Description
CRITICAL rule secure-storage flutter_secure_storage (Keychain/EncryptedSharedPreferences), 민감 데이터 저장
CRITICAL rule authentication 토큰 라이프사이클, 자동 갱신, biometric 인증, 세션 관리
HIGH rule ssl-pinning Dio SecurityContext, 인증서/공개키 pinning, 핀 업데이트 전략
HIGH rule api-key-protection --dart-define 빌드 주입, envied 패키지, 하드코딩 금지
HIGH rule obfuscation --obfuscate, ProGuard, dSYM, Crashlytics 심볼 업로드
MEDIUM rule data-protection 로컬 DB 암호화, 클립보드 보호, 스크린샷 방지
— ref mobile-security-checklist OWASP MASVS L1/L2 체크리스트, 추천 도구

Quick Rules

저장소 보안

  • 토큰/시크릿 → flutter_secure_storage (Keychain iOS / EncryptedSharedPreferences Android)
  • SharedPreferences에 민감 데이터 저장 금지 — 평문 저장, 루팅 시 노출
  • 로컬 DB → SQLCipher 또는 encrypt 패키지로 암호화

인증

  • Access Token (단수명) + Refresh Token (장수명) 분리
  • Dio interceptor로 401 감지 → 자동 갱신 → 재요청
  • Biometric → local_auth 패키지, 실패 시 PIN/패턴 폴백

전송 보안

  • TLS 1.2+ 필수, 인증서 pinning으로 MITM 차단
  • Dio SecurityContext + badCertificateCallback 조합
  • 핀 만료 대비 → 백업 핀 + 원격 업데이트 전략

API 키 보호

  • --dart-define=API_KEY=xxx → 빌드 시 주입
  • String.fromEnvironment('API_KEY') → 런타임 참조
  • .env → envied 패키지 (코드 생성, 난독화 옵션)
  • 하드코딩 → 절대 금지 (git history에 영구 노출)

난독화

  • flutter build --obfuscate --split-debug-info=debug-info/
  • Android: ProGuard/R8 shrinking 활성화
  • iOS: Bitcode (Xcode 설정) + dSYM 보관
  • Crashlytics → 디버그 심볼 업로드 (크래시 리포트 해석용)

Read the full file on GitHub · 87 lines

Files

What ships with it

7 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 1mo ago First seen · 87 lines · 36 tokens per session scan A 49355eaf9fd4

Subscribe to this mod's changes

security is a skill published in the GitHub repository sonature-lab/timsquad (12 stars, last pushed 1mo ago), licensed MIT. It adds 36 tokens to every session and 1,133 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 2026-08-30.

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