XSS_SKILL

XSS_SKILL is a skill for Claude Code, Codex from BugTraceAI/BugTraceAI-CLI. It costs 11 tokens per session (127 once invoked), scanned A, original, Apache-2.0.

A browser screenshot check for signs that cross-site scripting has inserted unexpected content or triggered a JavaScript dialog. Cross-site scripting is a web security flaw that injects attacker-controlled code into a page.

In plain words
What is it for?
It helps inspect screenshots for known marker text, alert popups, suspicious formatting, or injected domain text.
Why use it?
It provides a simple visual pass or fail signal for a specific injection test.

Skill for Claude CodeCodex

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

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/bugtraceai/bugtraceai-cli/xss
Any agent
npx skills add BugTraceAI/BugTraceAI-CLI --skill xss
Clone the repo
git clone --depth 1 https://github.com/BugTraceAI/BugTraceAI-CLI

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 XSS_SKILL

README.md
[![agentmods](https://agentmods.dev/badge/skills/bugtraceai/bugtraceai-cli/xss.svg)](https://agentmods.dev/skills/bugtraceai/bugtraceai-cli/xss)
Your own site
<a href="https://agentmods.dev/skills/bugtraceai/bugtraceai-cli/xss"><img src="https://agentmods.dev/badge/skills/bugtraceai/bugtraceai-cli/xss.svg" alt="Measured on agentmods" height="20"></a>
Per session 11 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 127 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 5.1 $0.00011 $0.00127
Opus 5 $0.00005 $0.00063
Sonnet 5 $0.00002 $0.00025
Haiku 4.5 $0.00001 $0.00013

Measured 2d ago against content hash 3e273ef7c067, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

XSS_SKILL 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 2d 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.

bugtrace/agents/system_prompts/xss_skill.md · 18 lines

What it actually says

XSS_SKILL

This is a browser screenshot. Look carefully at the page content. Is there ANY of the following visible on this page?

  1. Text containing 'BUGTRACE-XSS-CONFIRMED' or 'BUGTRACE-XSS'
  2. A JavaScript alert popup/dialog box
  3. Red colored text showing a domain name (like 'example.com')
  4. Any text that looks like it was injected (unusual formatting, yellow background).

Answer ONLY: YES or NO

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. 2d ago First seen · 18 lines · 11 tokens per session scan A 3e273ef7c067

Subscribe to this mod's changes

XSS_SKILL is a skill published in the GitHub repository BugTraceAI/BugTraceAI-CLI (184 stars, last pushed 3d ago), licensed Apache-2.0. It adds 11 tokens to every session and 127 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 2026-09-03.

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