A skill nobody finds in time is a skill you don't have. > TL;DR: Split every skill description into three sentences: when to read it, when to use it, and what it does. Common Mistake ❌ You write a skill description as one long paragraph. It expla...

Every rule you never delete outlives the reason you added it. > TL;DR: Audit your AGENTS.md and skills on a schedule, or you keep paying context rent on rules the model has outgrown. Common Mistake ❌ Every time the AI does something wrong, you add...

When all tests pass doesn't mean what you think it means. > TL;DR: Write the failing test first and ban deletions, or the AI deletes your test, reverts your fix, and calls it done. Common Mistake ❌ You ask the AI to fix a failing test, and it dele...

One broken window invites another > TL;DR: Don't reuse an existing getter to bolt on new business logic from outside the object. Problems 😔 Duplicated business ruleshttps://maximilianocontieri.com/code-smell-46-repeated-code Broken encapsulation ...

Build a factory where no human needs to work, keep the code coming, and place regular human audits. > TL;DR: Run your pipeline like a dark factory: automated, sampled, and policed by an adversarial model. Common Mistake ❌ You let one model write a...

The perfect prompt doesn't instruct the model on what it already knows how to do. > TL;DR: Reasoning models already verify and pace themselves, so drop those prompts and set real effort, scope, length, autonomy. Common Mistake ❌ You still write pr...

There's an industry trend to avoid writing code as much as possible, because who has time to write eight lines when a stranger already published a package for it. Turns out that convenience isn't free > TL;DR: Write your code unless you need an exis...

Approve the logic once, then let it run the same way forever. > TL;DR: Turn repeatable skill steps into tested scripts instead of prompts, so behavior stays deterministic and cheap. Common Mistake ❌ You ask the AI to repeat the same multi-step tas...

You can avoid null if you try > TL;DR: Don't use null for real places Problems 😔 Tight Coupling Unexpected Results Solutions 😃 1. Model unknown locations polymorphically Context 💬 Null Islandhttps://en.wikipedia.org/wiki/NullIsland is a fict...

Different stages need different brains. > TL;DR: Assign a different model to each pipeline stage since none excels at planning, coding, reviewing, and testing alike. Common Mistake ❌ You open one chat with your favorite model and ask it to plan, w...

One Second Brain doesn't scale past one skull. > TL;DR: Wire a skill into your company's live systems so every answer carries a source and a freshness check. Common Mistake ❌ As a single contributor, you can build a personal Second Brainhttps://co...

Style errors double when nobody enforces them. TL;DR: Wire your standards into hooks, skills, and a judge, so the harness blocks violations before a human opens the diff. Common Mistake ❌ You paste your coding standards into AGENTS.md and trust the...

Converting your anemic dictionaries is easy > TL;DR: Convert your key/value into full behavioral objects Problems Addressed 😔 Associative arrayshttps://maximilianocontieri.com/code-smell-27-associative-arrays Fail Fast principle violation Biject...

Know who speaks before the skill runs > TL;DR: Always define a clear role at the top of every skill file so you know whose perspective drives the execution. Common Mistake ❌ You write a skill full of rules but assign no role. The AI starts execut...

Everyone is talking about Loop Engineering. Apparently, you don't need to program anymore. > TL;DR: Loop Engineering is the hottest AI workflow pattern of 2026. But it hides a dirty secret. The Tweet That Started It All https://x.com/steipete/stat...

Brushing Over Real Problems > TL;DR: You write tests that touch every line but verify nothing, creating false confidence in a broken system. Problems 😔 False confidence Hidden production defectshttps://coderlegion.com/6337/we-need-to-stop-the-bug...

Comments are dead. Tests are alive > TL;DR: Take your comment, compact it, and name your functions. > Now test it and remove the comments. Problems Addressed 😔 Maintainability Readability Related Code Smells 💨 https://coderlegion.com/8106/code-...

Don't let the AI grade its own homework. > TL;DR: Spawn a fresh subagent after every task to check your rules, because the AI that did the work can't audit itself. Common Mistake ❌ You write a detailed AGENTS.mdhttps://coderlegion.com/13150/ai-cod...

You have a big algorithmic method. Let's break it. > TL;DR: Long methods are bad. Move them and break them. Problems Addressed 😔 Lack of Testability Accidental Complexity Testing Private Methodshttps://maximilianocontieri.com/code-smell-112-test...

Cap the size before the agent writes a single line. > TL;DR: Tell your AI to split work into small reviewable pull requests before it writes any code. Common Mistake ❌ You ask your AI agent to build a feature. The agent opens a 2,000-line pull re...