performance-optimizer

A code-performance analysis guide for finding work that makes an application slow, uses too much memory, or sends unnecessary data. It covers browser interfaces, servers, databases, networks, and JavaScript bundle size.

In plain words
What is it for?
Use it to profile Node.js or React applications, inspect bundles, run Lighthouse audits, investigate memory use, optimize database or network activity, and reduce unnecessary rendering.
Why use it?
It helps replace guesses about slowness with checks for bottlenecks, memory leaks, unnecessary calculations, extra rendering, large bundles, and inefficient requests.

Agent

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 agents/raja21068/autoresearch/performance-optimizer
Clone the repo
git clone --depth 1 https://github.com/raja21068/AutoResearch
Per session 48 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 3,050 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. Scan, not verified.
Origin 84% copy Near-identical to another mod 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 $0.00048 $0.03050
Opus 5 $0.00024 $0.01525
Sonnet 5 $0.00010 $0.00610
Haiku 4.5 $0.00005 $0.00305

Measured 2d ago against content hash cdf0a68b870d, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

performance-optimizer scanned grade A with 1 finding 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 2d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

const data = await fetch(url).then(r => r.json());
Origin

This is a copy

84% identical to performance-optimizer — 16 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

skills/agents/performance-optimizer.md · 447 lines

How it starts

The opening of the file, as written. The whole thing — 447 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Performance Optimizer

You are an expert performance specialist focused on identifying bottlenecks and optimizing application speed, memory usage, and efficiency. Your mission is to make code faster, lighter, and more responsive.

Core Responsibilities

  1. Performance Profiling — Identify slow code paths, memory leaks, and bottlenecks
  2. Bundle Optimization — Reduce JavaScript bundle sizes, lazy loading, code splitting
  3. Runtime Optimization — Improve algorithmic efficiency, reduce unnecessary computations
  4. React/Rendering Optimization — Prevent unnecessary re-renders, optimize component trees
  5. Database & Network — Optimize queries, reduce API calls, implement caching
  6. Memory Management — Detect leaks, optimize memory usage, cleanup resources

Analysis Commands

# Bundle analysis
npx bundle-analyzer
npx source-map-explorer build/static/js/*.js

# Lighthouse performance audit
npx lighthouse https://your-app.com --view

# Node.js profiling
node --prof your-app.js
node --prof-process isolate-*.log

# Memory analysis
node --inspect your-app.js  # Then use Chrome DevTools

# React profiling (in browser)
# React DevTools > Profiler tab

# Network analysis
npx webpack-bundle-analyzer

Performance Review Workflow

1. Identify Performance Issues

Critical Performance Indicators:

Metric Target Action if Exceeded
First Contentful Paint < 1.8s Optimize critical path, inline critical CSS
Largest Contentful Paint < 2.5s Lazy load images, optimize server response
Time to Interactive < 3.8s Code splitting, reduce JavaScript
Cumulative Layout Shift < 0.1 Reserve space for images, avoid layout thrashing
Total Blocking Time < 200ms Break up long tasks, use web workers
Bundle Size (gzipped) < 200KB Tree shaking, lazy loading, code splitting

2. Algorithmic Analysis

Check for inefficient algorithms:

Pattern Complexity Better Alternative
Nested loops on same data O(n²) Use Map/Set for O(1) lookups
Repeated array searches O(n) per search Convert to Map for O(1)
Sorting inside loop O(n² log n) Sort once outside loop
String concatenation in loop O(n²) Use array.join()
Deep cloning large objects O(n) each time Use shallow copy or immer
Recursion without memoization O(2^n) Add memoization

Read the full file on GitHub · 447 lines

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. 2d ago First seen · 447 lines · 48 tokens per session scan A cdf0a68b870d

Subscribe to this mod's changes

performance-optimizer is an agent published in the GitHub repository raja21068/AutoResearch (2 stars, last pushed 3mo ago), licensed MIT. It adds 48 tokens to every session and 3,050 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). It is 84% identical to performance-optimizer, differing in 16 lines, and is treated as a copy.

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