performance-profiling

Guidance for measuring and improving application speed. It uses tools such as Lighthouse, which audits web pages, and browser developer tools for inspecting runtime behavior.

In plain words
What is it for?
Investigating slow page loads, large build files, runtime delays, memory use, network requests, and key web experience measures such as loading, interaction, and layout stability.
Why use it?
It prevents guesswork by requiring a baseline measurement, identification of the bottleneck, a targeted change, and a follow-up check.

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/misonl/ling/performance-profiling
Any agent
npx skills add MisonL/Ling --skill performance-profiling
Clone the repo
git clone --depth 1 https://github.com/MisonL/Ling

Made for: Claude Code, Codex.

Per session 17 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,420 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00017 $0.01420
Opus 5 $0.00009 $0.00710
Sonnet 5 $0.00003 $0.00284
Haiku 4.5 $0.00002 $0.00142

Measured 2d ago against content hash f675493c20eb, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 2d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/lighthouse_audit.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

.agents/skills/performance-profiling/SKILL.md · 150 lines

How it starts

The opening of the file, as written. The whole thing — 150 lines — stays where its author put it; the contents beside it link to each section on GitHub.

性能分析

测量、分析、优化 —— 必须严格遵循此顺序。


运行脚本

执行以下脚本进行自动化性能分析:

脚本 用途 执行命令
scripts/lighthouse_audit.py Lighthouse(性能审计工具)审计 python scripts/lighthouse_audit.py https://example.com

1. 核心 Web 指标

核心 Web 指标(Core Web Vitals)用于衡量加载与交互质量。

目标值

指标 优(Good) 劣(Poor) 衡量维度
LCP < 2.5s > 4.0s 加载体验
INP < 200ms > 500ms 交互响应
CLS < 0.1 > 0.25 视觉稳定性

何时进行测量

阶段 工具选择
开发环境(Development) 本地 Lighthouse
CI/CD 流程 Lighthouse CI(持续集成)
生产环境(Production) RUM(真实用户监控,Real User Monitoring)

2. 性能分析工作流

四步走流程

1. 建立基准(Baseline)-> 测量当前状态
2. 识别瓶颈(Identify)-> 找出性能卡点
3. 实施修复(Fix)     -> 进行针对性改动
4. 验证改进(Validate)-> 确认性能提升

分析工具选择建议

待解决问题 推荐工具
页面加载速度 Lighthouse
打包体积(Bundle size) Bundle analyzer(包分析器)
运行时性能 DevTools(开发者工具)Performance(性能)面板
内存占用 DevTools(开发者工具)Memory(内存)面板
网络请求 DevTools(开发者工具)Network(网络)面板

3. 打包产物分析

观察重点

潜在问题 识别指标
巨大的外部依赖 位于打包产物顶部
冗余/重复代码 存在于多个 Chunk(代码块)中
未使用的代码 低覆盖率(Coverage)
缺失分包(Splitting) 产物呈现为一个巨大的单体文件

优化手段

发现的问题 对应动作
库文件过大 按需导入(Import specific modules)
依赖项重复 去重(Dedupe)、更新版本
主包代码包含路由逻辑 实施代码分割(Code split)
存在未引用的导出 启用 Tree shake(摇树优化)

Read the full file on GitHub · 150 lines

Files

What ships with it

1 file 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. 2d ago First seen · 150 lines · 17 tokens per session scan A f675493c20eb

Subscribe to this mod's changes

performance-profiling is a skill published in the GitHub repository MisonL/Ling (9 stars, last pushed 5mo ago), licensed MIT. It adds 17 tokens to every session and 1,420 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 2026-08-31.

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