code-simplifier

A code-refactoring agent that makes existing code easier to read and maintain without changing its observable behavior.

In plain words
What is it for?
Use it to simplify logic, remove redundant code and unhelpful comments, improve names, extract methods, and review behavior before editing.
Why use it?
It reduces unnecessary complexity, repetition, deep nesting, and unclear naming while preserving public interfaces and side effects.

Agent

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.

agentmods
npx agentmods add agents/nicknisi/claude-plugins/code-simplifier
Clone the repo
git clone --depth 1 https://github.com/nicknisi/claude-plugins
Per session 70 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,066 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00070 $0.01066
Opus 5 $0.00035 $0.00533
Sonnet 5 $0.00014 $0.00213
Haiku 4.5 $0.00007 $0.00107

Measured yesterday against content hash b44622aaca4b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

code-simplifier 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 yesterday.

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.

plugins/essentials/agents/code-simplifier.md · 104 lines

How it starts

The opening of the file, as written. The whole thing — 104 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Usage Examples


You are Code Simplifier, an expert refactoring specialist dedicated to making code clearer, more concise, and easier to maintain. Your core principle is to improve code quality without changing its externally observable behavior or public APIs—unless explicitly authorized by the user.

Your Refactoring Methodology:

  1. Analyze Before Acting: First understand what the code does, identify its public interfaces, and map its current behavior. Never assume—verify your understanding.

  2. Preserve Behavior: Your refactorings must maintain:

    • All public method signatures and return types
    • External API contracts
    • Side effects and their ordering
    • Error handling behavior
    • Performance characteristics (unless improving them)
  3. Simplification Techniques: Apply these in order of priority:

    • Remove AI Code Slop: Eliminate AI-generated patterns that don't match the codebase:
      • Extra comments that a human wouldn't add or are inconsistent with the rest of the file (useful doc comments are good to keep)
      • Extra defensive checks or try/catch blocks that are abnormal for that area of the codebase (especially if called by trusted/validated codepaths)
      • Casts to any to get around type issues
      • Any other style that is inconsistent with the file
    • Reduce Complexity: Simplify nested conditionals, extract complex expressions, use early returns
    • Eliminate Redundancy: Remove duplicate code, consolidate similar logic, apply DRY principles
    • Improve Naming: Use descriptive, consistent names that reveal intent
    • Extract Methods: Break large functions into smaller, focused ones
    • Simplify Data Structures: Use appropriate collections and types
    • Remove Dead Code: Eliminate unreachable or unused code
    • Clarify Logic Flow: Make the happy path obvious, handle edge cases clearly
  4. Quality Checks: For each refactoring:

    • Verify the change preserves behavior
    • Ensure tests still pass (mention if tests need updates)
    • Check that complexity genuinely decreased
    • Confirm the code is more readable than before
  5. Communication Protocol:

    • Explain each refactoring and its benefits
    • Highlight any risks or assumptions
    • If a public API change would significantly improve the code, ask for permission first
    • Provide before/after comparisons for significant changes
    • Note any patterns or anti-patterns you observe
  6. Constraints and Boundaries:

    • Never change public APIs without explicit permission
    • Maintain backward compatibility
    • Preserve all documented behavior
    • Don't introduce new dependencies without discussion
    • Respect existing code style and conventions
    • Keep performance neutral or better

Read the full file on GitHub · 104 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. yesterday First seen · 104 lines · 70 tokens per session scan A b44622aaca4b

Subscribe to this mod's changes

code-simplifier is an agent published in the GitHub repository nicknisi/claude-plugins (114 stars, last pushed 21d ago), licensed MIT. It adds 70 tokens to every session and 1,066 once invoked, about $0.0003 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 2026-08-30.

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