react-performance-debugging

react-performance-debugging is a skill for Claude Code, Codex from EtaYang10th/spark-skills. It costs 0 tokens per session (8,463 once invoked), scanned C, original, no licence file.

A workflow for finding and fixing slow pages and API routes in Next.js applications, including catalog, cart and comparison pages. It examines data fetching, background work, JavaScript bundle size and unnecessary component updates.

In plain words
What is it for?
Use it to investigate and improve performance in shopping pages and API routes without removing required test hooks or instrumentation.
Why use it?
It targets common causes of slow web applications while keeping required tests and performance tracking in place.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

Good fit Use it to investigate and improve performance in shopping pages and API routes without removing required test hooks or instrumentation.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/etayang10th/spark-skills/react-performance-debugging
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 EtaYang10th/spark-skills --skill react-performance-debugging
Clone the repo
git clone --depth 1 https://github.com/EtaYang10th/spark-skills

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 react-performance-debugging

README.md
[![agentmods](https://agentmods.dev/badge/skills/etayang10th/spark-skills/react-performance-debugging/github.svg)](https://agentmods.dev/skills/etayang10th/spark-skills/react-performance-debugging)
Your own site
<a href="https://agentmods.dev/skills/etayang10th/spark-skills/react-performance-debugging"><img src="https://agentmods.dev/badge/skills/etayang10th/spark-skills/react-performance-debugging/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 react-performance-debugging

Your own site · 80×15
<a href="https://agentmods.dev/skills/etayang10th/spark-skills/react-performance-debugging"><img src="https://agentmods.dev/badge/skills/etayang10th/spark-skills/react-performance-debugging.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 0 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 8,463 The whole file, excluding the scripts and references it only reads on demand.
Security scan C 3 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 $0.00000 $0.08463
Opus 5.5 $0.00000 $0.03385
Sonnet 5.5 $0.00000 $0.01693
Haiku 4.5 $0.00000 $0.00846

Measured 1mo ago against content hash 69bc08710954, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade C, and why

react-performance-debugging scanned grade C with 3 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 1mo 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.

Downloads and executes remote codehighSupply chain

curl | sh runs whatever the server returns today, which is not necessarily what it returned when this was reviewed.

curl -fsSL "$BASE_URL/api/products" | python3 -m json.tool | head -n 60

Makes network callslowCapability

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

const res = await fetch(url, {

Runs shell commandslowCapability

Expected in a hook, worth knowing in a rule or an instructions file.

const { execSync, spawn } = require("node:child_process");
spark_skills_gen/skills_gen_result/all_model_pdi/react-performance-debugging/SKILL.md · 1,260 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

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 1mo ago First seen · 1,260 lines · 0 tokens per session scan C 69bc08710954

Subscribe to this mod's changes

react-performance-debugging is a skill published in the GitHub repository EtaYang10th/spark-skills (109 stars, last pushed 4mo ago), with no licence file. It costs nothing until one of its globs matches a file; then it loads 8,463 tokens. A static security scan graded it C with 3 findings (downloads and executes remote code, makes network calls, runs shell commands). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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