visual-regression

visual-regression is a skill for Claude Code from aks-builds/quality-skills. It costs 120 tokens per session (2,808 once invoked), scanned A, original, MIT.

A guide to visual regression testing, which compares screenshots or page structures over time to catch unintended interface changes. It covers baseline images, dynamic content, and browser differences.

In plain words
What is it for?
Use it to plan or operate screenshot and DOM comparisons with tools such as Playwright, Cypress, Storybook, Percy, or similar systems. It helps manage baselines, masking, and browser coverage.
Why use it?
It catches visual problems that ordinary feature tests may miss, while helping avoid noisy tests that require constant manual maintenance.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the quality-skills plugin — 57 skills shipped together

Good fit Use it to plan or operate screenshot and DOM comparisons with tools such as Playwright, Cypress, Storybook, Percy, or similar systems. It helps manage baselines, masking, and browser coverage.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/aks-builds/quality-skills/visual-regression
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 aks-builds/quality-skills --skill visual-regression
Clone the repo
git clone --depth 1 https://github.com/aks-builds/quality-skills

Made for: Claude Code.

Or install quality-skills, the plugin that ships this one along with the rest of its 57 skills.

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 visual-regression

README.md
[![agentmods](https://agentmods.dev/badge/skills/aks-builds/quality-skills/visual-regression/github.svg)](https://agentmods.dev/skills/aks-builds/quality-skills/visual-regression)
Your own site
<a href="https://agentmods.dev/skills/aks-builds/quality-skills/visual-regression"><img src="https://agentmods.dev/badge/skills/aks-builds/quality-skills/visual-regression/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 visual-regression

Your own site · 80×15
<a href="https://agentmods.dev/skills/aks-builds/quality-skills/visual-regression"><img src="https://agentmods.dev/badge/skills/aks-builds/quality-skills/visual-regression.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 120 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,808 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.
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 $0.00120 $0.02808
Opus 5 $0.00060 $0.01404
Sonnet 5 $0.00024 $0.00562
Haiku 4.5 $0.00012 $0.00281

Measured 8d ago against content hash 075e2df30bcf, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

visual-regression 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 8d 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/visual-regression/SKILL.md · 327 lines

How it starts

The opening of the file, as written. The whole thing — 327 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Visual Regression Testing

You are an expert in visual regression testing — automated screenshot / DOM-snapshot comparisons that catch UI regressions automated functional tests miss. Your goal is to help engineers integrate visual testing without falling into the maintenance trap that has killed many visual-test programs. Don't fabricate tool features or pricing. When uncertain, point the reader to the vendor's docs.

Initial Assessment

Check .agents/qa-context.md (fallback: .claude/qa-context.md) before answering. Pay attention to:

  • Product type — design-system / component library, marketing site, app with heavy UI surface, server-rendered, mobile. Approaches differ.
  • Existing test stack — Playwright / Cypress / Storybook / Selenium / Detox. Integration patterns vary.
  • Visual change frequency — a stable design has a different cost profile than weekly redesigns.
  • Baselines storage — committed to repo, vendor-managed, or both.
  • Dynamic content — timestamps, ad slots, randomized content require masking.
  • Cross-browser need — Chrome only or all-engines.

If the file does not exist, ask: product type, existing test stack, design cadence, dynamic content extent, cross-browser requirement.


Why visual regression testing

Automated functional tests assert on selectors, text content, and state. They don't catch:

  • CSS regression (margin: 10px → 100px).
  • Z-index conflicts hiding elements visually.
  • Theme / dark-mode breakage.
  • Misaligned components.
  • Font fallback chains rendering differently.
  • Color shifts.
  • New unintended whitespace.

Visual regression compares rendered output (screenshots or DOM snapshots) against a baseline; differences flag as failures for review.

When not to invest:

  • Heavy redesign in progress — every test fails every day.
  • Small team that won't have capacity to triage baseline changes.
  • Pure backend / API project with no UI.

Approaches

1. Pixel-diff (full screenshot comparison)

Read the full file on GitHub · 327 lines

Files

What ships with it

1 file 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. 8d ago First seen · 327 lines · 120 tokens per session scan A 075e2df30bcf

Subscribe to this mod's changes

visual-regression is a skill published in the GitHub repository aks-builds/quality-skills (2 stars, last pushed 5d ago), licensed MIT. It adds 120 tokens to every session and 2,808 once invoked, about $0.0006 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 2026-08-31.

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