anti-patterns-catalog

anti-patterns-catalog is a skill for Claude Code, Codex from mickeyyaya/refactoring-skills. It costs 43 tokens per session (2,572 once invoked), scanned A, original, MIT.

A catalogue of recurring software design and architecture mistakes, called anti-patterns, with their symptoms and possible fixes.

In plain words
What is it for?
Use it during architecture reviews, legacy-system work, onboarding, or when changes repeatedly break unrelated parts of the application.
Why use it?
It helps connect repeated bugs, tangled ownership, and risky changes to deeper structural problems in the codebase.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it during architecture reviews, legacy-system work, onboarding, or when changes repeatedly break unrelated parts of the application.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/mickeyyaya/refactoring-skills/anti-patterns-catalog
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 mickeyyaya/refactoring-skills --skill anti-patterns-catalog
Clone the repo
git clone --depth 1 https://github.com/mickeyyaya/refactoring-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 anti-patterns-catalog

README.md
[![agentmods](https://agentmods.dev/badge/skills/mickeyyaya/refactoring-skills/anti-patterns-catalog/github.svg)](https://agentmods.dev/skills/mickeyyaya/refactoring-skills/anti-patterns-catalog)
Your own site
<a href="https://agentmods.dev/skills/mickeyyaya/refactoring-skills/anti-patterns-catalog"><img src="https://agentmods.dev/badge/skills/mickeyyaya/refactoring-skills/anti-patterns-catalog/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 anti-patterns-catalog

Your own site · 80×15
<a href="https://agentmods.dev/skills/mickeyyaya/refactoring-skills/anti-patterns-catalog"><img src="https://agentmods.dev/badge/skills/mickeyyaya/refactoring-skills/anti-patterns-catalog.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 43 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,572 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 $0.00043 $0.02572
Opus 5 $0.00022 $0.01286
Sonnet 5 $0.00009 $0.00514
Haiku 4.5 $0.00004 $0.00257

Measured 12d ago against content hash 69825257876d, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

anti-patterns-catalog 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 12d 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/anti-patterns-catalog/SKILL.md · 175 lines

How it starts

The opening of the file, as written. The whole thing — 175 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Software Anti-Patterns Catalog

Overview

Anti-patterns are recurring solutions that seem reasonable but cause more harm than good. Unlike code smells (surface indicators -- see detect-code-smells), anti-patterns describe complete failed solutions at class, module, or system scope. Each entry includes root cause, symptoms, and remediation with cross-references to fix skills.

When to Use

  • Architecture review reveals no clear ownership of responsibilities
  • A codebase is routinely described as "nobody dares touch that"
  • A single change requires coordinating edits across many files/teams
  • Bug fixes in one area consistently break unrelated areas

Quick Reference

Category Anti-Pattern Severity Primary Fix Skill
Design God Object CRITICAL refactor-moving-features
Design Golden Hammer HIGH design-patterns-creational-structural
Design Poltergeist MEDIUM refactor-moving-features
Design Blob HIGH refactor-moving-features
Development Spaghetti Code HIGH refactor-composing-methods
Development Copy-Paste Programming HIGH refactor-composing-methods, refactor-generalization
Development Lava Flow HIGH refactor-composing-methods
Development Boat Anchor MEDIUM refactor-moving-features
Development Magic Numbers/Strings MEDIUM refactor-organizing-data
Development Premature Optimization MEDIUM review-solid-clean-code
Development Cargo Cult Programming MEDIUM design-patterns-behavioral
Architecture Big Ball of Mud CRITICAL refactor-moving-features
Architecture Vendor Lock-in HIGH design-patterns-creational-structural
Architecture Singleton Overuse HIGH design-patterns-creational-structural

Design Anti-Patterns

God Object

  • Symptoms: 500-1000+ lines, name includes "Manager"/"Controller"/"Processor" with unbounded scope, any feature requires opening this file, 5+ unrelated method groups, untestable without mocking everything
  • Root Cause: Class started small; features added to the "closest existing class" without enforcing responsibility boundaries
  • Severity: CRITICAL -- single point of failure, merge conflict hotspot, primary source of Divergent Change
  • Remediation: Extract Class iteratively -- group related fields/methods into cohesive clusters, promote each to its own class. See refactor-moving-features. Related smells: Large Class, Divergent Change in detect-code-smells.

Read the full file on GitHub · 175 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. 12d ago First seen · 175 lines · 43 tokens per session scan A 69825257876d

Subscribe to this mod's changes

anti-patterns-catalog is a skill published in the GitHub repository mickeyyaya/refactoring-skills (6 stars, last pushed 5mo ago), licensed MIT. It adds 43 tokens to every session and 2,572 once invoked, about $0.0002 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.