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.
npx agentmods add skills/caspian-sun/claude-code-workflow/ext-perf-auditnpx skills add Caspian-Sun/claude-code-workflow --skill ext-perf-auditgit clone --depth 1 https://github.com/Caspian-Sun/claude-code-workflowWrote 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.
[](https://agentmods.dev/skills/caspian-sun/claude-code-workflow/ext-perf-audit)<a href="https://agentmods.dev/skills/caspian-sun/claude-code-workflow/ext-perf-audit"><img src="https://agentmods.dev/badge/skills/caspian-sun/claude-code-workflow/ext-perf-audit.svg" alt="Measured on agentmods" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00054 | $0.00692 |
| Opus 5 | $0.00027 | $0.00346 |
| Sonnet 5 | $0.00011 | $0.00138 |
| Haiku 4.5 | $0.00005 | $0.00069 |
Grade A, and why
ext-perf-audit 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.
How it starts
The opening of the file, as written. The whole thing — 79 lines — stays where its author put it; the contents beside it link to each section on GitHub.
ext-perf-audit — Performance Audit
You are now a frontend performance optimization expert. Perform a performance audit on the specified component / page / module.
Execution Approach
Run scripts to gather data first, then use AI for static analysis. Scripts handle measurement; AI handles pattern recognition.
Step 1: Build Artifact Analysis (if dist exists)
bash .claude/skills/ext-perf-audit/scripts/bundle-size.sh
Script output:
- Total size + chunks sorted by size
- List of JS files larger than 100KB
- List of asset files larger than 500KB (images / fonts)
AI identifies:
- Warnings for any single chunk > 500KB
- Images not compressed / not converted to WebP
- No route-level code splitting (e.g., an oversized
index.*.js)
Step 2: Dependency Size Quick Scan
bash .claude/skills/ext-perf-audit/scripts/heavy-deps.sh
The script lists the top 20 largest packages in node_modules. AI cross-references the "Common Bundle Killers" section in references/perf-checklist.md and provides recommendations.
Step 3: Static Code Scan (AI reads source)
Check the directory specified by $ARGUMENTS across the 5 dimensions in references/perf-checklist.md:
- Bundle size — full-library imports / duplicate dependencies / console.log / missing lazy loading
- Rendering performance — missing memo/useMemo/useCallback / missing keys / new references created in render path / state hoisted too high / JS doing CSS's job
- Network performance — serial requests that could be parallel / missing caching / image formats / missing prefetch
- Memory — useEffect missing cleanup / closures holding large objects / no virtual scrolling
- Initial load — blocking the critical path / missing Skeleton / waterfall requests
Output Format
🔴 Critical (impacts user experience):
- [file:line] Issue description
Impact: Estimated impact (e.g. +800ms on initial load / bundle +400KB)
Fix: Specific solution + code example
🟡 Moderate (worth optimizing):
- [file:line] Issue description
Fix: Solution
🔵 Suggestion (nice to have):
- [file:line] Issue description
📊 Overall: X/10, one-sentence summary
What ships with it
3 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.
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.
- 5d ago First seen · 79 lines · 54 tokens per session scan A da12510abb79
ext-perf-audit is a skill published in the GitHub repository Caspian-Sun/claude-code-workflow (10 stars, last pushed 5d ago), licensed MIT. It adds 54 tokens to every session and 692 once invoked, about $0.0003 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.
Other skills, from other repositories
password-spray-methodology
End-to-end password spray playbook. User enumeration, lockout detection, password pattern generation, spray execution across all protocols, error code differentials, and engagement discipline. Unifies M365/Entra, Okta, Exchange, Kerberos, SharePoint, XMLRPC, OIDC, and AD SMB/WinRM spraying into one methodology.
trellis-brainstorm
Guides collaborative requirements discovery before implementation. Creates task directory, seeds PRD, asks high-value questions one at a time, researches technical choices, and converges on MVP scope. Use when requirements are unclear, there are multiple valid approaches, or the user describes a new feature or complex…
vc-autopilot
Emit and validate the provisional goal block for Autopilot Mode. Owns the 9-field format and resume detection from a pasted goal block.
vc-audit-vc
Audit agent harness health: Claude/Codex agent parity, skill registry consistency, README.md sync, and protocol file wiring. Use when agents, skills, README.md, or development-protocol files move, split, or drift.
red-green-refactor
Guides the red-green-refactor TDD workflow: write a failing test first, implement the minimum code to make it pass, then refactor while keeping tests green. Use when a user asks to practice TDD, write tests first, follow red-green-refactor, do test-driven development, write failing tests before code, or phrases like…
skill-creator
Create new skills, modify and improve existing skills, and measure skill performance. Use when users want to create a skill from scratch, edit, or optimize an existing skill, run evals to test a skill, benchmark skill performance with variance analysis, or optimize a skill's description for better triggering accuracy.