performance-profiling

performance-profiling is a skill for Claude Code, Codex from fabioc-aloha/Alex_Skill_Mall. It costs 17 tokens per session (2,751 once invoked), scanned A, original, MIT.

A systematic process for measuring CPU, memory, and network use to find what makes software slow.

In plain words
What is it for?
Use it to investigate slow applications, locate hotspots, test optimizations, and monitor performance over time.
Why use it?
It replaces guesses about performance problems with measurements, a suspected bottleneck, and a verified improvement.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to investigate slow applications, locate hotspots, test optimizations, and monitor performance over time.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/fabioc-aloha/alex_skill_mall/performance-profiling
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.

Any agent
npx skills add fabioc-aloha/Alex_Skill_Mall --skill performance-profiling
Clone the repo
git clone --depth 1 https://github.com/fabioc-aloha/Alex_Skill_Mall

Made for: Claude Code, Codex.

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-profiling

README.md
[![agentmods](https://agentmods.dev/badge/skills/fabioc-aloha/alex_skill_mall/performance-profiling/github.svg)](https://agentmods.dev/skills/fabioc-aloha/alex_skill_mall/performance-profiling)
Your own site
<a href="https://agentmods.dev/skills/fabioc-aloha/alex_skill_mall/performance-profiling"><img src="https://agentmods.dev/badge/skills/fabioc-aloha/alex_skill_mall/performance-profiling/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for performance-profiling

Your own site · 80×15
<a href="https://agentmods.dev/skills/fabioc-aloha/alex_skill_mall/performance-profiling"><img src="https://agentmods.dev/badge/skills/fabioc-aloha/alex_skill_mall/performance-profiling.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 17 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,751 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 original 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 $0.00017 $0.02751
Opus 5 $0.00009 $0.01375
Sonnet 5 $0.00003 $0.00550
Haiku 4.5 $0.00002 $0.00275

Measured 5d ago against content hash 221b0fd9b8a6, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

performance-profiling 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.

plugins/code-quality/performance-profiling/skills/performance-profiling/SKILL.md · 440 lines

How it starts

The opening of the file, as written. The whole thing — 440 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Performance Profiling Skill

Find the bottleneck before optimizing. Measure twice, optimize once.


The Golden Rule

"Premature optimization is the root of all evil" — Donald Knuth

But also:

"Measure, don't guess" — Everyone who's optimized the wrong thing


Performance Investigation Flow

┌──────────────────────────────────────────────────────────┐
│  1. OBSERVE                                              │
│     User reports slowness → Reproduce → Measure baseline │
├──────────────────────────────────────────────────────────┤
│  2. IDENTIFY                                             │
│     Profile → Find hotspots → Determine bottleneck type  │
├──────────────────────────────────────────────────────────┤
│  3. HYPOTHESIZE                                          │
│     Why is this slow? → Form theory → Plan fix           │
├──────────────────────────────────────────────────────────┤
│  4. OPTIMIZE                                             │
│     Implement fix → Measure improvement → Verify         │
├──────────────────────────────────────────────────────────┤
│  5. MONITOR                                              │
│     Add metrics → Set alerts → Prevent regression        │
└──────────────────────────────────────────────────────────┘

Bottleneck Types

Type Symptoms Investigation
CPU-bound High CPU, reasonable memory Profile CPU, look for hot functions
Memory-bound High memory, GC pauses Heap profile, allocation tracking
I/O-bound Low CPU, waiting on disk/network Trace I/O operations, latency
Concurrency Low utilization, contention Thread dumps, lock analysis
Network High latency to external services Trace calls, measure RTT
Database Slow queries, connection wait Query plans, pool stats

CPU Profiling

Node.js

# Built-in profiler
node --prof app.js
node --prof-process isolate-*.log > processed.txt

# Chrome DevTools
node --inspect app.js
# Open chrome://inspect

# clinic.js (recommended)
npm install -g clinic
clinic doctor -- node app.js
clinic flame -- node app.js

Read the full file on GitHub · 440 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. 5d ago First seen · 440 lines · 17 tokens per session scan A 221b0fd9b8a6

Subscribe to this mod's changes

performance-profiling is a skill published in the GitHub repository fabioc-aloha/Alex_Skill_Mall (4 stars, last pushed yesterday), licensed MIT. It adds 17 tokens to every session and 2,751 once invoked, about $0.0001 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 2026-09-03.

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