pn-audit-performance-fe

pn-audit-performance-fe is a command for Claude Code, Cursor from perniemann/pnCore. It costs 44 tokens per session (630 once invoked), scanned A, original, MIT.

A review of the parts of a website that affect how quickly it loads and responds, including browser performance measures, JavaScript size, images, and blocking resources.

In plain words
What is it for?
Use it to check landing pages, application shells, or feature routes against performance targets and page-size budgets.
Why use it?
It helps find frontend causes of slow pages, layout movement, and delayed interactions.

Command for Claude CodeCursor

Written for Cursor and Claude Code: shipped in a Cursor plugin, but also a Claude Code command (commands/*.md).

Part of the pn-core plugin — 133 skills, 19 commands, 9 agents, 1 MCP server shipped together

Good fit Use it to check landing pages, application shells, or feature routes against performance targets and page-size budgets.

Compare 6 commands from other repositories ↓
Install with agentmods
npx agentmods add commands/perniemann/pncore/pn-audit-performance-fe
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.

Clone the repo
git clone --depth 1 https://github.com/perniemann/pnCore

Made for: Claude Code, Cursor.

Or install pn-core, the plugin that ships this one along with the rest of its 133 skills, 19 commands, 9 agents, 1 MCP server.

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 pn-audit-performance-fe

README.md
[![agentmods](https://agentmods.dev/badge/commands/perniemann/pncore/pn-audit-performance-fe/github.svg)](https://agentmods.dev/commands/perniemann/pncore/pn-audit-performance-fe)
Your own site
<a href="https://agentmods.dev/commands/perniemann/pncore/pn-audit-performance-fe"><img src="https://agentmods.dev/badge/commands/perniemann/pncore/pn-audit-performance-fe/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 pn-audit-performance-fe

Your own site · 80×15
<a href="https://agentmods.dev/commands/perniemann/pncore/pn-audit-performance-fe"><img src="https://agentmods.dev/badge/commands/perniemann/pncore/pn-audit-performance-fe.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 44 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 630 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 $0.00044 $0.00630
Opus 5 $0.00022 $0.00315
Sonnet 5 $0.00009 $0.00126
Haiku 4.5 $0.00004 $0.00063

Measured 7d ago against content hash b440371e0f29, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

pn-audit-performance-fe 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 7d 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.

packages/pn-core-mcp/content/commands/pn-audit-performance-fe.md · 68 lines

How it starts

The opening of the file, as written. The whole thing — 68 lines — stays where its author put it; the contents beside it link to each section on GitHub.

pn-audit-performance-fe

Start every response with: [pn-command] 🔺

Advanced (palette-hidden). Not in the / slash palette. Invoked by the /pn-frontend-audit umbrella, or directly via get_command("pn-audit-performance-fe").

Focused frontend performance pass: audit Core Web Vitals compliance, bundle composition, image strategy, render-blocking resources, and page-type budgets. No backend performance (use pn-audit-performance) — frontend only.

Flow

1. Context

Check .pncore-stack.md for framework (Next.js / Vite / Remix / etc.). Ask if scope unclear: "Which pages to audit? (landing / app shell / all routes)"

2. Audit

Load get_skill("pn-frontend-design-philosophy") for the performance budget framework (Phase 6).

Core Web Vitals targets:

  • LCP < 2.5s (largest contentful paint)
  • CLS < 0.1 (cumulative layout shift — reserved image dimensions?)
  • INP < 200ms (interaction to next paint)

Bundle:

  • Total JS budget per page type:
    • Landing/marketing: ≤ 150 KB compressed JS
    • App shell: ≤ 400 KB
    • Feature route: ≤ 250 KB
  • Code-split by route? Dynamic import() for heavy components?
  • Tree-shaking effective (no full library imports, e.g. import _ from 'lodash')?

Images:

  • Modern formats (WebP / AVIF) in use?
  • <img loading="lazy"> for below-fold?
  • width and height attributes set (prevents CLS)?
  • Hero images served at correct resolution (no 4K images for 400px containers)?

Render-blocking:

  • No synchronous <script> in <head> without defer / async?
  • Critical CSS inlined or preloaded?
  • Fonts preloaded with <link rel="preload">?

Caching:

  • Static assets have content-hash in filename (long Cache-Control)?
  • API responses cached appropriately (stale-while-revalidate)?

Output: numbered issues table (location | issue | impact | suggested fix). Save to docs/audits/.

Gate: Present issues for triage. Apply fixes after confirmation.

3. Fix

Apply in impact order: images → render-blocking → bundle splitting → caching.

Read the full file on GitHub · 68 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. 7d ago First seen · 68 lines · 44 tokens per session scan A b440371e0f29

Subscribe to this mod's changes

pn-audit-performance-fe is a command published in the GitHub repository perniemann/pnCore (0 stars, last pushed 2d ago), licensed MIT. It adds 44 tokens to every session and 630 once invoked, about $0.0002 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.