code-simplification

code-simplification is a skill for Claude Code, Codex from vanja-emichi/a0_agent_skills. It costs 51 tokens per session (2,388 once invoked), scanned A, original, MIT.

A code-refactoring guide for making working code easier to read and change without altering what it does. Refactoring means improving the internal structure of code while keeping its behavior the same.

In plain words
What is it for?
Use it for deeply nested logic, long functions, unclear names, scattered related code, or code that became harder to maintain after rushed changes.
Why use it?
It helps remove unnecessary complexity, duplication, and unclear structure from code that already works. It also discourages changes when the code is already clear or when simplification could slow it down.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions CLAUDE.md.

Good fit Use it for deeply nested logic, long functions, unclear names, scattered related code, or code that became harder to maintain after rushed changes.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/vanja-emichi/a0_agent_skills/code-simplification
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 vanja-emichi/a0_agent_skills --skill code-simplification
Clone the repo
git clone --depth 1 https://github.com/vanja-emichi/a0_agent_skills

Made for: Claude Code, Codex.

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 code-simplification

README.md
[![agentmods](https://agentmods.dev/badge/skills/vanja-emichi/a0_agent_skills/code-simplification/github.svg)](https://agentmods.dev/skills/vanja-emichi/a0_agent_skills/code-simplification)
Your own site
<a href="https://agentmods.dev/skills/vanja-emichi/a0_agent_skills/code-simplification"><img src="https://agentmods.dev/badge/skills/vanja-emichi/a0_agent_skills/code-simplification/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 code-simplification

Your own site · 80×15
<a href="https://agentmods.dev/skills/vanja-emichi/a0_agent_skills/code-simplification"><img src="https://agentmods.dev/badge/skills/vanja-emichi/a0_agent_skills/code-simplification.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 51 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,388 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 original 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 $0.00051 $0.02388
Opus 5.5 $0.00020 $0.00955
Sonnet 5.5 $0.00010 $0.00478
Haiku 4.5 $0.00005 $0.00239

Measured 1mo ago against content hash 81fb297135bd, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

code-simplification 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 1mo 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/code-simplification/SKILL.md · 265 lines

How it starts

The opening of the file, as written. The whole thing — 265 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Code Simplification

Overview

Simplify code by reducing complexity while preserving exact behavior. The goal is not fewer lines — it's code that is easier to read, understand, modify, and debug. Every simplification must pass a simple test: "Would a new team member understand this faster than the original?"

When to Use

  • After a feature is working and tests pass, but the implementation feels heavier than it needs to be
  • During code review when readability or complexity issues are flagged
  • When you encounter deeply nested logic, long functions, or unclear names
  • When refactoring code written under time pressure
  • When consolidating related logic scattered across files
  • After merging changes that introduced duplication or inconsistency

When NOT to use:

  • Code is already clean and readable — don't simplify for the sake of it
  • You don't understand what the code does yet — comprehend before you simplify
  • The code is performance-critical and the "simpler" version would be measurably slower
  • You're about to rewrite the module entirely — simplifying throwaway code wastes effort

The Five Principles

1. Preserve Behavior Exactly

Don't change what the code does — only how it expresses it. All inputs, outputs, side effects, error behavior, and edge cases must remain identical. If you're not sure a simplification preserves behavior, don't make it.

ASK BEFORE EVERY CHANGE:
→ Does this produce the same output for every input?
→ Does this maintain the same error behavior?
→ Does this preserve the same side effects and ordering?
→ Do all existing tests still pass without modification?

2. Follow Project Conventions

Simplification means making code more consistent with the codebase, not imposing external preferences. Before simplifying:

1. Read project conventions (CLAUDE.md or equivalent) using text_editor:read
2. Use code_execution_tool with grep -rn to study how neighboring code handles similar patterns
3. Match the project's style for imports, function declarations, naming, error handling

Read the full file on GitHub · 265 lines

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. 1mo ago First seen · 265 lines · 51 tokens per session scan A 81fb297135bd

Subscribe to this mod's changes

code-simplification is a skill published in the GitHub repository vanja-emichi/a0_agent_skills (5 stars, last pushed 2mo ago), licensed MIT. It adds 51 tokens to every session and 2,388 once invoked, about $0.0002 per session on Opus 5.5. 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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