perf-cop

perf-cop is a skill for Claude Code from oroddlokken/slop. It costs 120 tokens per session (5,718 once invoked), scanned A, original, no licence file.

A codebase-wide performance review that looks for slow operations, memory growth, delays, and other hot spots. It can also check the performance cost of a feature after it is added.

In plain words
What is it for?
It is for performance reviews, speed improvements, and investigations into hot loops, excess allocations, input/output batching, blocking work, and startup time.
Why use it?
It helps locate performance problems that may be spread across different parts of a codebase. It examines several kinds of bottlenecks instead of relying on a single suspected cause.

Skill for Claude Code

Written for Claude Code: disable-model-invocation in frontmatter.

Good fit It is for performance reviews, speed improvements, and investigations into hot loops…

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/oroddlokken/slop/perf-cop
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 oroddlokken/slop --skill perf-cop
Clone the repo
git clone --depth 1 https://github.com/oroddlokken/slop

Made for: Claude Code.

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 perf-cop

README.md
[![agentmods](https://agentmods.dev/badge/skills/oroddlokken/slop/perf-cop.svg)](https://agentmods.dev/skills/oroddlokken/slop/perf-cop)
Your own site
<a href="https://agentmods.dev/skills/oroddlokken/slop/perf-cop"><img src="https://agentmods.dev/badge/skills/oroddlokken/slop/perf-cop.svg" alt="Measured on agentmods" height="20"></a>
Per session 120 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,718 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 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 $0.00120 $0.05718
Opus 5 $0.00060 $0.02859
Sonnet 5 $0.00024 $0.01144
Haiku 4.5 $0.00012 $0.00572

Measured 6d ago against content hash 57fb8be41a8b, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

perf-cop 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 6d 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.

perf-cop/skills/perf-cop/SKILL.md · 236 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

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. 6d ago First seen · 236 lines · 120 tokens per session scan A 57fb8be41a8b

Subscribe to this mod's changes

perf-cop is a skill published in the GitHub repository oroddlokken/slop (2 stars, last pushed 17d ago), with no licence file. It adds 120 tokens to every session and 5,718 once invoked, about $0.0006 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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