# Coding Guidelines

Behavioral guidelines to reduce common LLM coding mistakes.

- Repository: https://github.com/tech-leads-club/agent-skills (7121 stars)
- Category: Design
- License: see repository
- Last updated: 2026-11-01
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add tech-leads-club/agent-skills --skill coding-guidelines -g -a claude-code -y`
Codex: `npx skills add tech-leads-club/agent-skills --skill coding-guidelines -g -a codex -y`
Cursor: `npx skills add tech-leads-club/agent-skills --skill coding-guidelines -g -a cursor -y`
Gemini CLI: `npx skills add tech-leads-club/agent-skills --skill coding-guidelines -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add tech-leads-club/agent-skills`

## Description

Behavioral guidelines to reduce common LLM coding mistakes. Use when writing, modifying, or reviewing code, implementation tasks, code changes, refactoring, bug fixes, or feature development. Do NOT use for architecture design, documentation, or non-code tasks.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Coding Guidelines

Behavioral guidelines to reduce common LLM coding mistakes. These principles bias toward caution over speed, for trivial tasks, use judgment.

## 1. Think Before Coding

**Don't assume. Don't hide confusion. Surface tradeoffs.**

Before implementing:

- State assumptions explicitly. If uncertain, ask.
- If multiple interpretations exist, present them, don't pick silently.
- If a simpler approach exists, say so. Push back when warranted.
- If something is unclear, stop. Name what's confusing. Ask.
- Disagree honestly. If the user's approach seems wrong, say so, don't be sycophantic.

## 2. Simplicity First

**Minimum code that solves the problem. Nothing speculative.**

- No features beyond what was asked.
- No abstractions for single-use code.
- No "flexibility" or "configurability" that wasn't requested.
- No error handling for impossible scenarios.
- If you write 200 lines and it could be 50, rewrite it.

Ask yourself: "Would a senior engineer say this is overcomplicated?" If yes, simplify.

## 3. Surgical Changes

**Touch only what you must. Clean up only your own mess.**

When editing existing code:

- Don't "improve" adjacent code, comments, or formatting.
- Don't refactor things that aren't broken.
- Match existing style, even if you'd do it differently.
- If you notice unrelated dead code, mention it, don't delete it.

When your changes create orphans:

- Remove imports/variables/functions that YOUR changes made unused.
- Don't remove pre-existing dead code unless asked.

**The test:** Every changed line should trace directly to the user's request.

## 4. Goal-Driven Execution

**Define success criteria. Loop until verified.**

Transform tasks into verifiable goals:

- "Add validation" → "Write tests for invalid inputs, then make them pass"
- "Fix the bug" → "Write a test that reproduces it, then make it pass"
- "Refactor X" → "Ensure tests pass before and after"

For multi-step tasks, state a brief plan:

The rest: https://github.com/tech-leads-club/agent-skills/blob/HEAD/packages/skills-catalog/skills/(development)/coding-guidelines/SKILL.md