reduce

reduce is a skill for Claude Code from escoffier-labs/skillet. It costs 79 tokens per session (1,781 once invoked), scanned A, a copy of reduce, MIT.

A code-cleanup method that makes code clearer while preserving its behavior. It requires checking that the same inputs, outputs, side effects, errors, interface, and evaluation order remain intact.

In plain words
What is it for?
Simplifying, tidying, or refactoring code for readability when the intended behavior must stay exactly the same.
Why use it?
It reduces unnecessary complexity without quietly changing what the software does. Tests or other evidence provide a safety check for the cleanup.

Skill for Claude Code

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

Part of the skillet plugin — 39 skills, 1 hook shipped together

Good fit Simplifying, tidying, or refactoring code for readability when the intended behavior must stay exactly the same.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/escoffier-labs/skillet/reduce
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 escoffier-labs/skillet --skill reduce
Clone the repo
git clone --depth 1 https://github.com/escoffier-labs/skillet

Made for: Claude Code.

Or install skillet, the plugin that ships this one along with the rest of its 39 skills, 1 hook.

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 reduce

README.md
[![agentmods](https://agentmods.dev/badge/skills/escoffier-labs/skillet/reduce/github.svg)](https://agentmods.dev/skills/escoffier-labs/skillet/reduce)
Your own site
<a href="https://agentmods.dev/skills/escoffier-labs/skillet/reduce"><img src="https://agentmods.dev/badge/skills/escoffier-labs/skillet/reduce/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 reduce

Your own site · 80×15
<a href="https://agentmods.dev/skills/escoffier-labs/skillet/reduce"><img src="https://agentmods.dev/badge/skills/escoffier-labs/skillet/reduce.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 79 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,781 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 98% copy Near-identical to another mod 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 $0.00079 $0.01781
Opus 5 $0.00039 $0.00890
Sonnet 5 $0.00016 $0.00356
Haiku 4.5 $0.00008 $0.00178

Measured 9d ago against content hash 521238bb4be4, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

reduce 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 9d 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.

Origin

This is a copy

98% identical to reduce — 2 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

skillet/skills/reduce/SKILL.md · 110 lines

How it starts

The opening of the file, as written. The whole thing — 110 lines — stays where its author put it; the contents beside it link to each section on GitHub.

reduce

A reduction simmers a sauce to drive off the water and concentrate the flavor, and the dish tastes the same, only sharper. You do that to code: boil off the excess, concentrate the intent, and the behavior comes out identical. The cook who reduces too hard scorches the pan and changes the dish; the discipline is knowing when to pull it off the heat.

Core principle: same inputs, same outputs, same side effects, same errors, same public interface, same evaluation order. If the behavior moved, it was not a reduction, it was a rewrite. No behavior-preservation evidence, no applied simplification. Violating the letter of that is violating its spirit.

The behavior lock

Before you change a single line, establish the lock. This is the whole safety story; everything else is taste.

  1. Pin the scope. Default to the code that recently changed (see Scope). Know exactly which files and functions you are reducing before you start.
  2. Find the tests that cover it. Run them and confirm they exercise the code you are about to touch. If coverage is thin, write characterization tests first (taste) that capture the current behavior, edge cases included, only when that is safe and in scope. If you cannot lock the behavior with tests, drop to report mode.
  3. Baseline-verify green. Run the suite and read the output before touching anything. You are proving the starting point, not assuming it.
  4. Reduce in small steps, one category of simplification at a time (see What to reduce).
  5. Re-run the same verification after each meaningful change. Evidence in hand before any "behavior unchanged" claim (check). A reduction you did not re-run is a hypothesis.
  6. Cannot lock it? Switch to report mode or ask the user. Never apply a simplification you cannot prove safe.

Two modes

Apply is the default for recently changed code that has tests, or where characterization tests can be added safely. You make the edits, one category per commit, with the verification evidence.

Read the full file on GitHub · 110 lines

Files

What ships with it

2 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.

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. 9d ago First seen · 110 lines · 79 tokens per session scan A 521238bb4be4

Subscribe to this mod's changes

reduce is a skill published in the GitHub repository escoffier-labs/skillet (4 stars, last pushed 8d ago), licensed MIT. It adds 79 tokens to every session and 1,781 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. It is 98% identical to reduce, differing in 2 lines, and is treated as a copy.

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