code-simplifier

name	code-simplifier
description	Simplify recently modified code for clarity, consistency, and maintainability without changing behavior. Detects languages from changed files and applies language-specific simplification rules alongside general principles.

Code Simplifier

Simplify recently modified code for clarity, consistency, and maintainability -- without changing behavior.

Step 1: Identify Modified Files

Look at the git context provided by the command (unstaged, staged, untracked). Filter to source files only -- ignore images, configs, lockfiles, generated files, etc.

If the user provided arguments (e.g. a commit range or file list), use those instead.

Step 2: Detect Languages and Load Rules

Map file extensions to languages and read the matching rule files from this skill's rules/ directory:

• .ts, .tsx, .js, .jsx, .mjs, .cjs -> rules/typescript.md
• .py, .pyi -> rules/python.md
• .rb, .erb, .rake -> rules/ruby.md
• .go -> rules/go.md
• .ex, .exs, .heex -> rules/elixir.md
• .rs -> rules/rust.md
• .java -> rules/java.md

Only read rule files for languages actually present in the modified files. If no rule file exists for a language, use only the general principles below.

Step 3: Check for Project Standards

If AGENTS.md or CLAUDE.md exists at the project root, read it. Project-specific coding standards take highest priority over bundled language rules.

Step 4: Simplify

Read each modified source file and apply these principles:

• Preserve functionality. Never change what the code does -- only how it does it.
• Reduce nesting. Use early returns and guard clauses to flatten deeply nested code.
• Eliminate dead code. Remove unreachable code, unused variables, unused imports, and redundant abstractions.
• Improve naming. Use descriptive names for variables, functions, and parameters.
• Simplify comments. Remove comments that describe obvious code. Keep comments that explain WHY.
• Avoid nested ternaries. Prefer if/else or switch/match for multiple conditions.
• Choose clarity over brevity. Explicit code is better than clever one-liners.
• Don't combine unrelated concerns. Each function should do one thing.
• Don't over-simplify. Removing a useful abstraction is a regression, not a simplification.
• Consolidate duplication. Extract repeated logic -- but only if the extraction is clearer.
• Prefer standard library. Replace custom reimplementations with well-known standard library equivalents.
• Minimize scope. Move variable declarations closer to their usage.

Also apply any language-specific rules loaded in Step 2.

Step 5: Verify

Ensure all changes are behavior-preserving. If unsure whether a change alters behavior, do not make it.