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 skills add berkcangumusisik/claude-code-practices --skill perf-auditgit clone --depth 1 https://github.com/berkcangumusisik/claude-code-practicesWrote 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/berkcangumusisik/claude-code-practices/perf-audit)<a href="https://agentmods.dev/skills/berkcangumusisik/claude-code-practices/perf-audit"><img src="https://agentmods.dev/badge/skills/berkcangumusisik/claude-code-practices/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 | $0.00025 | $0.00279 |
| Opus 5 | $0.00013 | $0.00139 |
| Sonnet 5 | $0.00005 | $0.00056 |
| Haiku 4.5 | $0.00003 | $0.00028 |
Grade A, and why
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 8d 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.
What it actually says
Performance Audit
Target: $1 (or src/ if not specified)
Database / API
- N+1 query patterns (loop with query inside)
- Missing indexes (queries on non-indexed columns)
- Fetching all fields when only a few are needed (
SELECT *) - Sequential async calls that could be parallel (
Promise.all)
Frontend
- Expensive computations on every render (should use
useMemo) - Event listeners added without cleanup
- Large imports not code-split (
import * from) - Images without lazy loading or size hints
General
- Synchronous operations that block the event loop
- Memory leaks (closures holding references)
- Redundant data transformation loops (can be combined)
- Missing caching for expensive operations
For each finding:
- Show the problematic code
- Explain the performance impact
- Show the fix
- Estimate improvement (rough order of magnitude)
Prioritize by impact: fix things that run in hot paths (request handlers, render functions, loops) first.
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.
- 8d ago First seen · 41 lines · 25 tokens per session scan A 367c38be7e5e
perf-audit is a skill published in the GitHub repository berkcangumusisik/claude-code-practices (10 stars, last pushed 4mo ago), licensed MIT. It adds 25 tokens to every session and 279 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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