performance-optimization

performance-optimization is a skill for Claude Code from sunnypatneedi/claude-starter-kit. It costs 33 tokens per session (2,734 once invoked), scanned A, original, no licence file.

A guide to finding and fixing slow parts of web applications, both in the browser and on servers. It covers profiling, caching, database tuning, splitting code, and improving Core Web Vitals, which are Google's measures of website loading and responsiveness.

In plain words
What is it for?
Use it to investigate performance problems, improve frontend and backend speed, tune database work, and make key web performance measurements better.
Why use it?
It helps locate the causes of slow pages, slow server responses, and poor loading experiences instead of relying on guesswork.

Skill for Claude Code

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

Part of the claude-starter-kit plugin — 42 skills shipped together

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.

agentmods
npx agentmods add skills/sunnypatneedi/claude-starter-kit/performance-optimization
Any agent
npx skills add sunnypatneedi/claude-starter-kit --skill performance-optimization
Clone the repo
git clone --depth 1 https://github.com/sunnypatneedi/claude-starter-kit

Made for: Claude Code.

Or install claude-starter-kit, the plugin that ships this one along with the rest of its 42 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 performance-optimization

README.md
[![agentmods](https://agentmods.dev/badge/skills/sunnypatneedi/claude-starter-kit/performance-optimization.svg)](https://agentmods.dev/skills/sunnypatneedi/claude-starter-kit/performance-optimization)
Your own site
<a href="https://agentmods.dev/skills/sunnypatneedi/claude-starter-kit/performance-optimization"><img src="https://agentmods.dev/badge/skills/sunnypatneedi/claude-starter-kit/performance-optimization.svg" alt="Measured on agentmods" height="20"></a>
Per session 33 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,734 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 $0.00033 $0.02734
Opus 5 $0.00016 $0.01367
Sonnet 5 $0.00007 $0.00547
Haiku 4.5 $0.00003 $0.00273

Measured 5d ago against content hash 75ec5dad72ef, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

performance-optimization 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 5d 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/engineering/performance-optimization/SKILL.md · 459 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 5d ago First seen · 459 lines · 33 tokens per session scan A 75ec5dad72ef

Subscribe to this mod's changes

performance-optimization is a skill published in the GitHub repository sunnypatneedi/claude-starter-kit (11 stars, last pushed 6mo ago), with no licence file. It adds 33 tokens to every session and 2,734 once invoked, about $0.0002 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 2026-08-30.

Related

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