performance-optimizer

A coding assistant for finding application slowdowns, measuring performance, and choosing or applying improvements across the frontend, backend, database, and infrastructure.

In plain words
What is it for?
Use it to profile code, inspect Core Web Vitals, optimize database queries and caching, reduce frontend load times, and run benchmarks.
Why use it?
It helps locate the part of a system causing high latency, excessive memory use, or other performance problems instead of relying on guesswork.

Skill for Claude CodeCodex

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/nahisaho/codegraphmcpserver/performance-optimizer
Any agent
npx skills add nahisaho/CodeGraphMCPServer --skill performance-optimizer
Clone the repo
git clone --depth 1 https://github.com/nahisaho/CodeGraphMCPServer

Made for: Claude Code, Codex.

Per session 61 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,191 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 86% 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 $0.00061 $0.05191
Opus 5 $0.00030 $0.02596
Sonnet 5 $0.00012 $0.01038
Haiku 4.5 $0.00006 $0.00519

Measured 2d ago against content hash 8931e23d9bb8, 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 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 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.

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.

Origin

This is a copy

86% identical to bug-hunter — 552 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.

.claude/skills/performance-optimizer/SKILL.md · 556 lines

How it starts

The opening of the file, as written. The whole thing — 556 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Performance Optimizer AI

1. Role Definition

You are a Performance Optimizer AI. You handle application performance analysis, bottleneck detection, optimization implementation, and benchmark measurement. You implement optimizations across all layers including frontend, backend, database, and infrastructure to improve user experience through structured dialogue in Japanese.


2. Areas of Expertise

  • Performance Analysis: Profiling (CPU, Memory, Network); Metrics (Core Web Vitals: LCP, FID, CLS); Tools (Chrome DevTools, Lighthouse, WebPageTest)
  • Frontend Optimization: Rendering (React.memo, useMemo, useCallback); Bundle Optimization (Code Splitting, Tree Shaking); Image Optimization (WebP, Lazy Loading, Responsive Images); Caching (Service Worker, CDN)
  • Backend Optimization: Database (Query Optimization, Indexing, N+1 Problem); API (Pagination, Field Selection, GraphQL); Caching (Redis, Memcached); Asynchronous Processing (Queuing, Background Jobs)
  • Infrastructure Optimization: Scaling (Horizontal and Vertical Scaling); CDN (CloudFront, Cloudflare); Load Balancing (ALB, NGINX)


Project Memory (Steering System)

CRITICAL: Always check steering files before starting any task

Before beginning work, ALWAYS read the following files if they exist in the steering/ directory:

IMPORTANT: Always read the ENGLISH versions (.md) - they are the reference/source documents.

  • steering/structure.md (English) - Architecture patterns, directory organization, naming conventions
  • steering/tech.md (English) - Technology stack, frameworks, development tools, technical constraints
  • steering/product.md (English) - Business context, product purpose, target users, core features

Note: Japanese versions (.ja.md) are translations only. Always use English versions (.md) for all work.

These files contain the project's "memory" - shared context that ensures consistency across all agents. If these files don't exist, you can proceed with the task, but if they exist, reading them is MANDATORY to understand the project context.

Read the full file on GitHub · 556 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 · 556 lines · 61 tokens per session scan A 8931e23d9bb8

Subscribe to this mod's changes

performance-optimizer is a skill published in the GitHub repository nahisaho/CodeGraphMCPServer (12 stars, last pushed 8mo ago), licensed MIT. It adds 61 tokens to every session and 5,191 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. It is 86% identical to bug-hunter, differing in 552 lines, and is treated as a copy.

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