skills-ui-debug-agent

skills-ui-debug-agent is a skill for Claude Code, Codex from anhtester/claude-testing-kit. It costs 40 tokens per session (2,373 once invoked), scanned A, a copy of UI Debug Agent, MIT.

A set of instructions for inspecting web or mobile interfaces in a real browser and finding reliable ways to identify screen elements.

In plain words
What is it for?
Use it to inspect page structure, find Playwright, Selenium, or Appium locators, debug automation tests, and capture screenshots or other evidence.
Why use it?
It helps explain failures such as missing elements, blocked clicks, timeouts, changing page content, frames, and shadow DOM.

Skill for Claude CodeCodex

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/anhtester/claude-testing-kit/skills-ui-debug-agent
Any agent
npx skills add anhtester/claude-testing-kit --skill skills-ui-debug-agent
Clone the repo
git clone --depth 1 https://github.com/anhtester/claude-testing-kit

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 skills-ui-debug-agent

README.md
[![agentmods](https://agentmods.dev/badge/skills/anhtester/claude-testing-kit/skills-ui-debug-agent.svg)](https://agentmods.dev/skills/anhtester/claude-testing-kit/skills-ui-debug-agent)
Your own site
<a href="https://agentmods.dev/skills/anhtester/claude-testing-kit/skills-ui-debug-agent"><img src="https://agentmods.dev/badge/skills/anhtester/claude-testing-kit/skills-ui-debug-agent.svg" alt="Measured on agentmods" height="20"></a>
Per session 40 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,373 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 94% copy Near-identical to another mod 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 $0.00040 $0.02373
Opus 5 $0.00020 $0.01187
Sonnet 5 $0.00008 $0.00475
Haiku 4.5 $0.00004 $0.00237

Measured 4d ago against content hash d7ea150a2d4c, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

skills-ui-debug-agent 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.

Origin

This is a copy

94% identical to UI Debug Agent — 12 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.claude/skills/skills-ui-debug-agent/SKILL.md · 234 lines

How it starts

The opening of the file, as written. The whole thing — 234 lines — stays where its author put it; the contents beside it link to each section on GitHub.

UI Debug Agent

Description

Skill chuyên biệt giúp agent inspect ứng dụng web/mobile trực tiếp trên browser thật, phân tích DOM, thu thập locators ổn định, và debug các vấn đề UI automation.

Agent có thể:

  • Mở browser thật, navigate đến bất kỳ URL nào
  • Inspect DOM elements — xác định attributes, hierarchy, state
  • Thu thập locators ổn định cho Playwright, Selenium, Appium
  • Debug automation failures (element not found, click intercepted, timeout)
  • Capture UI state (snapshot, screenshot) để phân tích
  • Phân tích dynamic content, iframe, shadow DOM, SPA navigation

When to Use

Sử dụng skill này khi:

  • Cần khám phá UI của một trang web/module mới
  • Cần tìm locator cho element cụ thể
  • Cần debug test automation fail do UI thay đổi
  • Cần verify locator có hoạt động trên DOM thực tế không
  • Cần phân tích DOM để hiểu cấu trúc UI (forms, tables, modals)
  • Cần capture evidence (screenshot) cho test report

Trigger keywords: "inspect UI", "tìm locator", "debug element", "mở browser xem", "kiểm tra DOM"


MCP Command Sequence (BẮT BUỘC)

Khi sử dụng Playwright MCP để debug UI, LUÔN tuân theo thứ tự:

1. browser_navigate(url)           → Mở trang
2. browser_resize(1920, 1080)      → Desktop viewport
3. browser_wait_for(text/time)     → Chờ page load
4. browser_snapshot()              → Thu thập DOM (dùng để phân tích + tìm locator)
5. browser_click/type/hover(ref)   → Tương tác (nếu cần)
6. browser_take_screenshot()       → Chụp ảnh (evidence khi fail hoặc milestone)

Quy tắc quan trọng:

Quy tắc Chi tiết
KHÔNG navigate lại nếu đã ở đúng trang Tránh reload ngoài ý muốn
LUÔN resize ngay sau navigate browser_resize(1920, 1080) — đảm bảo desktop viewport
LUÔN wait trước khi snapshot Chờ page load hoàn tất
Dùng snapshot để phân tích Snapshot trả về accessibility tree — nhanh, chính xác, có ref để tương tác
Dùng screenshot để báo cáo Screenshot là hình ảnh — dùng khi cần evidence visual

Read the full file on GitHub · 234 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. 4d ago First seen · 234 lines · 40 tokens per session scan A d7ea150a2d4c

Subscribe to this mod's changes

skills-ui-debug-agent is a skill published in the GitHub repository anhtester/claude-testing-kit (50 stars, last pushed 26d ago), licensed MIT. It adds 40 tokens to every session and 2,373 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 94% identical to UI Debug Agent, differing in 12 lines, and is treated as a copy.