From Magento 2 / Mage-OS Skills
Performance audit of a Magento 2 / Mage-OS / Adobe Commerce storefront: full-page cache misses and cacheable="false" leaks, Varnish/Redis configuration, indexer modes and cron health, TTFB, payload sizes, and Core Web Vitals. Use this skill whenever the user says a Magento store is slow, asks to audit/review/check storefront performance, mentions FPC or cache hit rate, X-Magento-Cache-Debug, Varnish not caching, high TTFB, stuck or realtime indexers, cron problems, or Core Web Vitals / PageSpeed scores for a Magento or Mage-OS site. Works from a URL alone, from a codebase alone, or both. For writing or fixing module code, use the magento-module skill instead.
How this skill is triggered — by the user, by Claude, or both
Slash command
/magento-skills:magento-auditThe summary Claude sees in its skill listing — used to decide when to auto-load this skill
Audit procedure for Magento storefront performance. The output is always a severity-ranked
Audit procedure for Magento storefront performance. The output is always a severity-ranked markdown report (references/scoring.md) where every finding carries verbatim evidence and an exact fix — never a list of generic tips.
The cardinal rule: audit caching first. Until full-page cache works, every other number (TTFB, CWV, server load) is measuring the wrong thing. Most "Magento is slow" reports are FPC failures with a different hat on.
| You have | Mode | Tools |
|---|---|---|
| A store URL | URL mode | scripts/check-headers.py, browser/Lighthouse if available |
| The codebase (and ideally a running install) | Codebase mode | scripts/scan-layout.py, env.php, bin/magento CLI |
| Both | Combined — do URL mode first, use codebase mode to explain what it found | both |
Ask for the missing half only if the findings demand it (e.g. URL mode shows MISSes → request codebase access to find the killer); otherwise audit what you have and record the gap in the report's "Not audited" section.
Collect 3–5 public URLs: homepage, a category page, a product page, a CMS page. Never test cart/checkout/account pages for cache hits — they are uncacheable by design.
Run the header check (stdlib-only Python, two requests per URL so the second is warm):
python scripts/check-headers.py https://store.example/ https://store.example/some-category \
[--insecure] # for local/dev self-signed certs
It measures TTFB cold/warm, payload size, compression, and parses
X-Magento-Cache-Debug / Age / Varnish headers into pre-classified findings.
Interpret with references/fpc-audit.md — particularly the header table and what a warm MISS means.
Frontend layer: read references/frontend-perf.md; run Lighthouse/PageSpeed if available, otherwise estimate from the fetched HTML (script/CSS counts, LCP image preload, lazy-loading mistakes, third-party tags).
FPC killers — scan layout XML for cacheable="false":
python scripts/scan-layout.py /path/to/magento [--include-vendor] [--json]
Severity is pre-classified (default.xml → critical, catalog/CMS handles → critical,
checkout/customer → info). For runtime killers the scan can't see
(isScopePrivate, session starts in frontend blocks), follow
references/fpc-audit.md.
env.php and stack — read app/etc/env.php against
references/server-config.md: cache/session backends and
Redis DB separation, http_cache_hosts, deploy mode, OPcache. Never quote secrets
(passwords, keys) from env.php into the report — name the key, not the value.
Indexers & cron — with a running install:
bin/magento indexer:show-mode # any 'realtime' on production = finding
bin/magento indexer:status
bin/magento cache:status # full_page enabled?
bin/magento deploy:mode:show
plus the cron_schedule checks in
references/indexers-cron.md. Without a running install,
audit crontab.xml groups and env.php cron_consumers_runner statically and note the
rest as not-audited.
Assemble findings using the template and scoring rubric in references/scoring.md. Non-negotiables:
The deliverable is the report. Don't start editing layout XML or env.php unless the user
asks for fixes — then switch to the magento-module skill conventions for any code
changes, and re-run the relevant script afterwards to prove the finding is gone.
If the elgentos magento2-dev-mcp MCP server is connected, prefer it for reading merged
layout/config when chasing an FPC killer — Magento merges XML across modules and themes,
and the single-file view can mislead.
npx claudepluginhub staksoft/magento-claude-skills --plugin magento-skillsProvides behavioral guidelines to reduce common LLM coding mistakes, focusing on simplicity, surgical changes, assumption surfacing, and verifiable success criteria.
Searches, retrieves, and installs Agent Skills from prompts.chat registry using MCP tools like search_skills and get_skill. Activates for finding skills, browsing catalogs, or extending Claude.
Creates, edits, and optimizes skills for Claude Code, including drafting, evaluating with test prompts, iterating on performance, and improving skill descriptions for better triggering accuracy.