web-app

web-app is a skill for Claude Code, Codex from Strategic-Automation/violin. It costs 13 tokens per session (521 once invoked), scanned A, original, MIT.

A web-application security testing guide for finding input-handling and browser-side flaws. It covers problems such as SQL injection, cross-site scripting, command injection, and unsafe file or template processing.

In plain words
What is it for?
Use it when checking web routes, request fields, uploads, parsers, templates, or browser code for injection and related client-side vulnerabilities.
Why use it?
It helps identify places where user-controlled data could run unintended code, access files or services, or be interpreted unsafely. It routes each problem to the relevant testing guide.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it when checking web routes, request fields, uploads, parsers, templates, or browser code for injection and related client-side vulnerabilities.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/strategic-automation/violin/web-app
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 Strategic-Automation/violin --skill web-app
Clone the repo
git clone --depth 1 https://github.com/Strategic-Automation/violin

Made for: Claude Code, Codex.

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 web-app

README.md
[![agentmods](https://agentmods.dev/badge/skills/strategic-automation/violin/web-app/github.svg)](https://agentmods.dev/skills/strategic-automation/violin/web-app)
Your own site
<a href="https://agentmods.dev/skills/strategic-automation/violin/web-app"><img src="https://agentmods.dev/badge/skills/strategic-automation/violin/web-app/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 web-app

Your own site · 80×15
<a href="https://agentmods.dev/skills/strategic-automation/violin/web-app"><img src="https://agentmods.dev/badge/skills/strategic-automation/violin/web-app.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 13 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 521 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. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00013 $0.00521
Opus 5 $0.00006 $0.00260
Sonnet 5 $0.00003 $0.00104
Haiku 4.5 $0.00001 $0.00052

Measured 9d ago against content hash 77400b33beee, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

web-app 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.

skills/web-app/SKILL.md · 53 lines

What it actually says

Web Application Security Testing

On-demand skill for web application input-validation and client-side vulnerability classes. The pentest orchestrator routes here when a discovered surface matches one class below. Load only the matched playbook with read_file; do not eagerly load every playbook.

When to Use

  • A web route, parameter, body field, upload, parser, template, or client-side sink is in scope.
  • Recon identifies an injection sink, unsafe deserialization, XML parser, or JavaScript object merge.
  • Do not use for authorization/session flaws, API protocol coverage, or workflow abuse; use the routed specialist skill.

Playbook Routing

Class Playbook
SQL Injection playbooks/sqli.md
Cross-Site Scripting playbooks/xss.md
Command Injection playbooks/command-injection.md
Server-Side Request Forgery playbooks/ssrf.md
Path Traversal / LFI playbooks/path-traversal.md
Server-Side Template Injection playbooks/ssti.md
XXE / XML Entity Injection playbooks/xxe.md
NoSQL Injection playbooks/nosql-injection.md
LDAP Injection playbooks/ldap-injection.md
XPath Injection playbooks/xpath-injection.md
Prototype Pollution playbooks/prototype-pollution.md
Insecure Deserialization playbooks/deserialization.md
Improper Input Validation playbooks/input-validation.md

Common Pitfalls

  • Run target-touching checks only through the authorized Violin execution tools.
  • Read the matched playbook's stop conditions before validation.
  • Store redacted proof under $ENG_DIR/evidence/exploitation/<class>/.

Verification Checklist

  • Engagement bootstrap and scope validation succeeded.
  • The matched playbook alone was loaded and bound to the PTT task.
  • Evidence captures the baseline and the decisive differential response.
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 · 53 lines · 13 tokens per session scan A 77400b33beee

Subscribe to this mod's changes

web-app is a skill published in the GitHub repository Strategic-Automation/violin (85 stars, last pushed 5d ago), licensed MIT. It adds 13 tokens to every session and 521 once invoked, about $0.0001 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 2026-08-30.

Related

Other skills, from other repositories

performing-jwt-none-algorithm-attack

Execute and test the JWT none algorithm attack to bypass signature verification by manipulating the alg header field in JSON Web Tokens.

xalgorix/xalgorix · 34 tokens

Web Application Security Testing

OWASP Top 10 testing, injection vulnerability detection, API security assessment, authentication testing, and web vulnerability reporting for authorized assessments.

Masriyan/Claude-Code-CyberSecurity-Skill · 30 tokens

bypassing-authentication-with-forced-browsing

Discovering and accessing unprotected pages, APIs, and administrative interfaces by enumerating URLs and bypassing authentication controls during authorized security assessments.

26zl/cybersec-toolkit · 39 tokens

kali-pentest-zh

A Chinese-language guide for carrying out authorized penetration tests with Kali Linux command-line tools through a local system, SSH, or Docker.

x-glacier/kali-pentest · 87 tokens

kali-pentest

Execute authorized penetration testing via Kali Linux CLI tools over SSH or Docker. Covers: information gathering, vulnerability analysis, sniffing & spoofing, web/API testing, exploitation, password attacks, wireless, cloud-native security, RFID/NFC, VoIP/ICS, reverse engineering, forensics, post-exploitation/C2, and…

x-glacier/kali-pentest · 73 tokens

api-security-testing

Security-test a REST, GraphQL, or gRPC API with Strix — autonomous agents that enumerate endpoints from an OpenAPI/GraphQL schema (or by crawling), then actually exploit the API-specific vulnerability classes in the OWASP API Security Top 10 (2023) — broken object-level authorization (BOLA/IDOR), broken object…

usestrix/strix · 144 tokens