performance-and-web-vitals SKILL.md skillB
performance-and-web-vitals from dembrandt/dembrandt-skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add dembrandt/dembrandt-skills/performance-and-web-vitals@git:20261001.b05848aPins git:20261001.b05848a in mdr.lock. Pin the fingerprint instead.
- Audit grade
- B, 16 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- dembrandt/dembrandt-skills
- Path
skills/performance-and-web-vitals/SKILL.md- Versions recorded
- 2
- Latest version
- git:20261001.b05848a, committed Oct 1, 2026
- First version recorded
- Apr 19, 2026
- Size
- 8,015 bytes
- Repository stars
- 183
- License
- MIT
Lighthouse audits and Core Web Vitals — LCP, CLS, INP. Use when optimising page load, layout shift, input delay, images, fonts or render-blocking resources.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Performance and Web Vitals ## Run a Lighthouse Audit ```bash # CLI audit — outputs JSON and HTML report npx lighthouse https://example.com --output html --output-path ./lighthouse-report.html # Headless, useful in CI npx lighthouse https://example.com --chrome-flags="--headless" --output json --output-path ./report.json # Audit specific categories only npx lighthouse https://example.com --only-categories=performance,accessibility,seo ``` Or open Chrome DevTools → Lighthouse tab → Analyse page load. **Target scores:** | Category | Target | |---|---| | Performance | ≥ 90 | | Accessibility | 100 | | Best Practices | ≥ 95 | | SEO | ≥ 95 | --- ## Core Web Vitals ### LCP — Largest Contentful Paint *How fast does the main content appear?* **Target: ≤ 2.5s** LCP measures when the largest visible element (hero image, heading, video poster) renders. It is the user's perception of "did the page load?" **Common causes and fixes:** | Cause | Fix | |---|---| | Unoptimised hero image | Use WebP/AVIF, correct size, `fetchpriority="high"` | | Image not preloaded | `<link rel="preload" as="image" href="hero.webp">` | …
Read the whole file at its exact version.
How to install
mdr add dembrandt/dembrandt-skills/performance-and-web-vitals@sha256:f934ccf0b8c5a1c1The line at the top of this page pins the label git:20261001.b05848a, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_jl5p4gokly2mg7zz)
3 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 2 versions of this file, between Apr 19, 2026 and Oct 1, 2026, about one every 165 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20261001.b05848a latest | 2026-10-01 | b05848a | 8,015 B | B | view · diff |
| git:20260419.3cf6904 | 2026-04-19 | 3cf6904 | 8,118 B | B | view |
Audit of the latest version
- fail: No script tag (matched: <script)
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (8015 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
Starting a new one? Use a template for SKILL.md on mdpantry, which passes every one of these checks and says what to change in it.
Source
dembrandt/dembrandt-skills · 183 stars · license MIT · pushed 2026-11-01 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_jl5p4gokly2mg7zz GET https://markdownregistry.com/api/v1/resolve?ref=dembrandt/dembrandt-skills/performance-and-web-vitals GET https://markdownregistry.com/api/v1/blob/f934ccf0b8c5a1c150eb2cf2a533f3b1b433883e46f54df967fa6b6da3419637
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.