agentmods.dev

client-side

client-side is a skill for Claude Code, Codex from transilienceai/communitytools. It costs 38 tokens per session (355 once invoked), scanned A, original, MIT.

A guide to testing vulnerabilities in the browser side of web applications, including cross-site scripting, cross-site request forgery, unsafe cross-origin rules, clickjacking, and prototype pollution.

In plain words
What is it for?
It helps trace browser data flows, test reflected, stored, and DOM-based XSS, check CSRF and CORS protections, test clickjacking and prototype pollution, and record remediation steps.
Why use it?
It helps find attacks caused by how JavaScript, browser permissions, and user-controlled input interact. It also requires confirming the issue and documenting how to reproduce and fix it.

Skill for Claude CodeCodex

Part of the communitytools plugin — 42 skills, 5 commands, 9 agents, 1 hook shipped together

not rated 507 +4 1mo ago A scan 38 tokens original MIT
View the source file transilienceai/communitytools
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 skills/transilienceai/communitytools/client-side
Any agent
npx skills add transilienceai/communitytools --skill client-side
Clone the repo
git clone --depth 1 https://github.com/transilienceai/communitytools

Made for: Claude Code, Codex.

Or install communitytools, the plugin that ships this one along with the rest of its 42 skills, 5 commands, 9 agents, 1 hook.

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 client-side

README.md
[![agentmods](https://agentmods.dev/badge/skills/transilienceai/communitytools/client-side.svg)](https://agentmods.dev/skills/transilienceai/communitytools/client-side)
Your own site
<a href="https://agentmods.dev/skills/transilienceai/communitytools/client-side"><img src="https://agentmods.dev/badge/skills/transilienceai/communitytools/client-side.svg" alt="Measured on agentmods" height="20"></a>
Per session 38 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 355 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00038 $0.00355
Opus 5 $0.00019 $0.00178
Sonnet 5 $0.00008 $0.00071
Haiku 4.5 $0.00004 $0.00036

Measured 4d ago against content hash ecd9761b4770, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

client-side 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.

skills/client-side/SKILL.md · 38 lines

What it actually says

Client-Side

Test for client-side vulnerabilities across modern web applications and SPAs.

Techniques

Type Key Vectors
XSS Reflected, Stored, DOM-based, framework-specific (React, Vue, Angular)
CSRF Token bypass, SameSite cookie bypass, cross-origin requests
CORS Misconfigured origins, null origin, wildcard credentials
Clickjacking Frame-based, drag-and-drop, multi-step
DOM-based DOM sinks, source/sink analysis, JavaScript URL schemes
Prototype Pollution Client-side gadgets, server-side pollution, property injection

Workflow

  1. Identify input sources and data flows
  2. Classify sink contexts (HTML, attribute, URL, JS, CSS)
  3. Enumerate defenses (encoding, CSP, sanitizers, Trusted Types)
  4. Craft context-appropriate payloads
  5. Validate execution and demonstrate impact
  6. Document with reproduction steps and remediation

Reference

  • reference/xss*.md - XSS bypass techniques and exploitation
  • reference/csrf*.md - CSRF techniques and bypasses
  • reference/cors*.md - CORS misconfiguration testing
  • reference/clickjacking*.md - Clickjacking techniques
  • reference/dom*.md - DOM-based vulnerability testing
  • reference/prototype-pollution*.md - Prototype pollution techniques
Files

What ships with it

44 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. 4d ago First seen · 38 lines · 38 tokens per session scan A ecd9761b4770

Subscribe to this mod's changes

client-side is a skill published in the GitHub repository transilienceai/communitytools (507 stars, last pushed 1mo ago), licensed MIT. It adds 38 tokens to every session and 355 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 2026-08-30.

Design and UXSecurityTestingbounty-huntershackeronepentestpentest-toolsecurity-research
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