ag-skills: Agent for Claude Code

.agent/agents/performance-optimizer.md

performance-optimizer is an agent for Claude Code from duongnguyen321/ag-skills. It costs 53 tokens per session (1,068 once invoked), scanned A, original, no licence file.

A performance specialist for finding and reducing causes of slow software. It covers profiling, runtime speed, memory and CPU use, browser performance metrics, and bundle size.

In plain words
What is it for?
Use it to improve loading speed, reduce JavaScript bundle size, optimize runtime performance, and investigate Lighthouse or Core Web Vitals results.
Why use it?
It helps locate what makes an application slow or resource-heavy and guides targeted improvements.

Agent for Claude Code

Written for Claude Code: a Claude Code subagent (agents/*.md). Also seen: model in frontmatter.

This is duongnguyen321/ag-skills's own configuration. It tells Claude Code how to work on ag-skills itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything ag-skills configures →

Reuse

Borrowing it

Nothing to install: this file belongs to duongnguyen321/ag-skills. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/duongnguyen321/ag-skills/main/.agent/agents/performance-optimizer.md
Clone the repo
git clone --depth 1 https://github.com/duongnguyen321/ag-skills

Made for: Claude Code.

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-optimizer

README.md
[![agentmods](https://agentmods.dev/badge/agents/duongnguyen321/ag-skills/performance-optimizer.svg)](https://agentmods.dev/agents/duongnguyen321/ag-skills/performance-optimizer)
Your own site
<a href="https://agentmods.dev/agents/duongnguyen321/ag-skills/performance-optimizer"><img src="https://agentmods.dev/badge/agents/duongnguyen321/ag-skills/performance-optimizer.svg" alt="Measured on agentmods" height="20"></a>
Per session 53 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,068 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00053 $0.01068
Opus 5 $0.00026 $0.00534
Sonnet 5 $0.00011 $0.00214
Haiku 4.5 $0.00005 $0.00107

Measured 7d ago against content hash 967089346570, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

performance-optimizer 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 7d 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.

.agent/agents/performance-optimizer.md · 188 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

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. 7d ago First seen · 188 lines · 53 tokens per session scan A 967089346570

Subscribe to this mod's changes

performance-optimizer is an agent published in the GitHub repository duongnguyen321/ag-skills (2 stars, last pushed 20d ago), with no licence file. It adds 53 tokens to every session and 1,068 once invoked, about $0.0003 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 2026-08-31.

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