Frontend Performance Audit
What it does
Takes your real performance numbers (from Lighthouse or PageSpeed Insights) and your page, and tells you the specific thing that’s actually slow — and the concrete fix — instead of a generic “optimize your images” list.
When to use it
- Your page feels slow and you have (or can get) real metrics
- Lighthouse flagged something and you don’t know what to change
- Before launch, to catch the obvious wins
The skill
Act as a web performance engineer. Rules: work only from the real
numbers and code I give you — do NOT invent metrics or guess at
values I didn't provide; if you need a number I don't have, tell me
how to get it (Lighthouse / PageSpeed Insights / DevTools). Rank
fixes by likely impact, and be honest when a "problem" is actually
fine. No made-up percentages.
My real metrics (paste what you have — Lighthouse/PSI): [LCP, CLS,
INP/TBT, total page weight, request count — whatever I actually have]
What the page is: [DESCRIBE, and paste the <head> and any big
scripts/styles if you can]
What feels slow to me: [FIRST PAINT / JANK ON SCROLL / SLOW TAP /
JUST THE SCORE]
Give me:
1. The diagnosis: which metric is actually bad vs which is fine,
read from MY numbers — no invented data.
2. The likely cause in my specific page (render-blocking resource,
unsized image causing CLS, heavy script, no caching, etc.),
pointing at the actual code I pasted where possible.
3. The fix list, ranked by expected impact, each with the concrete
change to make — not "optimize images" but "add width/height to
the hero img and serve it as WebP".
4. What to re-measure after each fix to confirm it worked.
5. The honest note: anything that's already good and not worth
touching, so I don't waste effort chasing a green score.Example output
[TO FILL AFTER TESTING]
Tweaks
- Get real numbers first: run the page through PageSpeed Insights and paste the results — the audit is only as good as the data
- Fix one thing, re-measure, then the next; bulk changes hide which one helped
- A perfect score isn’t the goal — a page that feels fast to real users is; the skill will tell you when to stop