measure-before-optimizing

measure-before-optimizing is a skill for Claude Code from yuchi-chang/no-cape. It costs 23 tokens per session (334 once invoked), scanned A, original, no licence file.

A skill that requires measuring code performance before changing it for speed.

In plain words
What is it for?
Use it when improving performance or before optimizing code believed to be slow.
Why use it?
It helps prevent optimizing code based only on guesses about what is slow.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the no-cape plugin — 14 skills, 1 command, 3 hooks shipped together

Good fit Use it when improving performance or before optimizing code believed to be slow.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/yuchi-chang/no-cape/measure-before-optimizing
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 yuchi-chang/no-cape --skill measure-before-optimizing
Clone the repo
git clone --depth 1 https://github.com/yuchi-chang/no-cape

Made for: Claude Code.

Or install no-cape, the plugin that ships this one along with the rest of its 14 skills, 1 command, 3 hooks.

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 measure-before-optimizing

README.md
[![agentmods](https://agentmods.dev/badge/skills/yuchi-chang/no-cape/measure-before-optimizing.svg)](https://agentmods.dev/skills/yuchi-chang/no-cape/measure-before-optimizing)
Your own site
<a href="https://agentmods.dev/skills/yuchi-chang/no-cape/measure-before-optimizing"><img src="https://agentmods.dev/badge/skills/yuchi-chang/no-cape/measure-before-optimizing.svg" alt="Measured on agentmods" height="20"></a>
Per session 23 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 334 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 $0.00023 $0.00334
Opus 5 $0.00012 $0.00167
Sonnet 5 $0.00005 $0.00067
Haiku 4.5 $0.00002 $0.00033

Measured 8d ago against content hash a4750a6f7276, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

measure-before-optimizing 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.

skills/measure-before-optimizing/SKILL.md · 27 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

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. 8d ago First seen · 27 lines · 23 tokens per session scan A a4750a6f7276

Subscribe to this mod's changes

measure-before-optimizing is a skill published in the GitHub repository yuchi-chang/no-cape (2 stars, last pushed 1mo ago), with no licence file. It adds 23 tokens to every session and 334 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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