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.
npx skills add HoangNguyen0403/agent-skills-standard --skill common-web-visual-testinggit clone --depth 1 https://github.com/HoangNguyen0403/agent-skills-standardWrote 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.
[](https://agentmods.dev/skills/hoangnguyen0403/agent-skills-standard/common-web-visual-testing)<a href="https://agentmods.dev/skills/hoangnguyen0403/agent-skills-standard/common-web-visual-testing"><img src="https://agentmods.dev/badge/skills/hoangnguyen0403/agent-skills-standard/common-web-visual-testing/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.
<a href="https://agentmods.dev/skills/hoangnguyen0403/agent-skills-standard/common-web-visual-testing"><img src="https://agentmods.dev/badge/skills/hoangnguyen0403/agent-skills-standard/common-web-visual-testing.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00052 | $0.00625 |
| Opus 5 | $0.00026 | $0.00313 |
| Sonnet 5 | $0.00010 | $0.00125 |
| Haiku 4.5 | $0.00005 | $0.00063 |
Grade A, and why
common-web-visual-testing 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 12d 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.
How it starts
The opening of the file, as written. The whole thing — 58 lines — stays where its author put it; the contents beside it link to each section on GitHub.
🌐 Web Visual & Behavioral Testing
Priority: P1 (HIGH)
[!IMPORTANT] Tier 2 (Methodology): Strategy web UI/UX audit. Tier 3 (Domain): Responsive, A11y (WCAG), Browser Engine quirk.
🧪 Testing Mindset (Comparative Audit)
Visual test best as Comparative Audit loop:
- Baseline (Before): Capture
snapshot --aria+screenshotprod/main. - Implementation (After): Capture same local/feature.
- Audit: Compare state for regression, CLS, Aria drift.
Responses must label the two captures as Before and After (or Baseline and Fixed) and include the diff and neighboring-element side-effect check.
📋 Scenario Matrix
| Change Type | Scenarios to Run |
|---|---|
| CSS/Layout | Responsive Audit + Hover + CLS Check |
| Forms/Input | Validation Msg + Focus State + Error Boundary |
| Navigation | URL Sync + Sticky Header + Back-Button Persistence |
| Assets/Fonts | Lazy Load + Icon Check + LCP Audit |
| Accessibility | Tab Order + Aria-Snapshot + Color Contrast |
🚫 Anti-Patterns
- Single-Viewport: Never verify Desktop only. Check Mobile (375px) + Tablet (768px).
- Ignore Layout Shift: Check loading state (skeleton) → no page jump.
- Unmasked Dynamic: MUST mask timestamp/balance via
--maskor JS (opacity: 0). Avoid "False Regression". - Blind Assertion: Use
playwright-cli snapshot --ariaverify state before done. - External Dependency: Mock/bypass 3rd-party (Chat, Analytics) → prevent flakiness.
🔗 References
- playwright-cli: playwright-cli
- Diagnostic Decoder: diagnostic-decoder
- DOM vs Screenshot: dom-snapshot-vs-screenshot
- Login & Data: login-and-test-data
- Scenario Details: scenarios
What ships with it
4 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.
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.
- 12d ago First seen · 58 lines · 52 tokens per session scan A efb7a53d4287
common-web-visual-testing is a skill published in the GitHub repository HoangNguyen0403/agent-skills-standard (565 stars, last pushed 2d ago), licensed MIT. It adds 52 tokens to every session and 625 once invoked, about $0.0003 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.
Other skills, from other repositories
server-side-calls
Call tRPC procedures directly from server code using t.createCallerFactory() and router.createCaller(context) for integration testing, internal server logic, and custom API endpoints. Catch TRPCError and extract HTTP status with getHTTPStatusCodeFromError(). Error handling via onError option.
verify
Build/launch/drive recipe for verifying apps/docs changes at runtime (demos, docs pages, llms.txt).
testing
Skill "testing" from udecode/plate-playground-template, covering testing goal, core rules, seam selection, fixtures and assertions and quick reference.
playtest
Drive a real browser against a game with vg playtest: smoke checks, scripted bot playtests, softlock detection, screenshots and visual diffs, on localhost or a deployed URL.
debug
Structured bug diagnosis and fixing workflow that reproduces, diagnoses root cause, applies a minimal fix, writes regression tests, and scans for similar patterns.
nextjs-development
Next.js 16.2.4 with TypeScript — App Router, Server Components, use cache directive, Turbopack dev, Server Actions, ISR, SSR, SSG, MCP devtools, metadata API, route handlers, instrumentation.