visual-validation

visual-validation is a skill for Claude Code, Codex from alinaqi/maggy. It costs 0 tokens per session (769 once invoked), scanned A, original, MIT.

A screenshot-based check for web interface changes that captures the result and compares it with an earlier image to find visual regressions.

In plain words
What is it for?
It helps capture browser or application windows, compare before-and-after screenshots, and report whether a visual regression was found.
Why use it?
It catches unintended changes to the appearance of a page after code is edited, such as altered layout or styling.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions Claude Code.

Good fit It helps capture browser or application windows, compare before-and-after screenshots, and report…

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Install with agentmods
npx agentmods add skills/alinaqi/maggy/visual-validation
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 alinaqi/maggy --skill visual-validation
Clone the repo
git clone --depth 1 https://github.com/alinaqi/maggy

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 visual-validation

README.md
[![agentmods](https://agentmods.dev/badge/skills/alinaqi/maggy/visual-validation.svg)](https://agentmods.dev/skills/alinaqi/maggy/visual-validation)
Your own site
<a href="https://agentmods.dev/skills/alinaqi/maggy/visual-validation"><img src="https://agentmods.dev/badge/skills/alinaqi/maggy/visual-validation.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 769 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. 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 $0.00000 $0.00769
Opus 5 $0.00000 $0.00385
Sonnet 5 $0.00000 $0.00154
Haiku 4.5 $0.00000 $0.00077

Measured 3d ago against content hash 724554860827, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

visual-validation scanned grade A with 1 finding 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 3d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

3. Wait for health: curl -s http://localhost:8080/api/health
skills/visual-validation/SKILL.md · 87 lines

How it starts

The opening of the file, as written. The whole thing — 87 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Visual Validation — Autonomous Screenshot Verification

Philosophy

Every UI change should be visually verified before it ships. Peekaboo captures pixel-accurate screenshots. The system compares before/after and flags visual regressions. No manual "looks good to me" — the machine verifies what the machine built.

Autonomous Flow

static/* files modified (detected by auto-review-hook or E2E testkit)
    ↓
peekaboo image --mode screen → ~/.maggy/visual-verify/after-{ts}.png
    ↓
Compare with latest baseline (previous after-*.png)
    ↓
AI evaluation: Gemini Flash analyzes screenshot for visual regressions
    ↓
Report: CLEAN or REGRESSION_DETECTED with specific issues

Quick Commands

# Install
brew install steipete/tap/peekaboo

# Capture full system screenshot
peekaboo image --mode screen --retina --path /tmp/screen.png

# Capture specific window
peekaboo image --mode window --app "Google Chrome" --path /tmp/window.png

# Verify Maggy dashboard after code change
peekaboo image --mode window --app "Google Chrome" --path ~/.maggy/visual-verify/after-$(date -u +%Y%m%d-%H%M%S).png

# Compare two screenshots
ls -la ~/.maggy/visual-verify/after-*.png  # review before/after pairs

Autonomous Verification Flow (Claude Code)

# After making any static/ file change, Claude should:
1. git add maggy/maggy/static/ && git diff --stat HEAD  # check what changed
2. Restart Maggy: lsof -ti :8080 | xargs kill && python3 -m maggy.main &
3. Wait for health: curl -s http://localhost:8080/api/health
4. Capture screenshot: peekaboo image --mode screen --path ~/.maggy/visual-verify/after-$(date -u +%Y%m%d-%H%M%S).png
5. Compare with latest baseline in ~/.maggy/visual-verify/
6. AI evaluation: ~/bin/gemini-api --flash "Analyze this screenshot for visual regressions"
7. Report findings

Maggy Dashboard Verification

# One-shot verification
curl -s http://localhost:8080/api/health && \
peekaboo image --mode screen --path ~/.maggy/visual-verify/verify.png && \
echo "✓ Dashboard verified — screenshot at ~/.maggy/visual-verify/verify.png"

Read the full file on GitHub · 87 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. 3d ago First seen · 87 lines · 0 tokens per session scan A 724554860827

Subscribe to this mod's changes

visual-validation is a skill published in the GitHub repository alinaqi/maggy (705 stars, last pushed 19d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 769 tokens. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

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