/simplify-code

name: simplify-code
description: "Parallel 3-agent cleanup of recent code changes."
version: 1.0.0
author: Hermes Agent (inspired by Claude Code /simplify)
license: MIT
platforms: [linux, macos, windows]
metadata:
  hermes:
    tags: [code-review, cleanup, refactor, delegation, subagent, parallel, simplify]
    related_skills: [requesting-code-review, test-driven-development, plan]

Simplify Code — Parallel Review & Cleanup

Review your recent code changes with three focused reviewers running in parallel, aggregate their findings, and apply the fixes worth applying.

**Core principle:** Three narrow reviewers beat one broad reviewer. Each one deeply searches the codebase for a single class of problem — reuse, quality, efficiency — without diluting its attention across all three. They run concurrently, so you pay the latency of one review, not three.

When to Use

Trigger this skill when the user says any of:

• "simplify" / "simplify my changes" / "simplify these changes"
• "review my code" / "review my recent changes" / "clean up my changes"
• "/simplify" (if they're carrying the Claude Code habit over)

Optional modifiers the user may add — honor them:

• **Focus:** "simplify focus on efficiency" → run only the efficiency reviewer

(or weight the aggregation toward it). Recognized focuses: `reuse`, `quality`, `efficiency`.

• **Dry run:** "simplify but don't change anything" / "just report" → run the

three reviewers, present findings, apply NOTHING. Ask before applying.

• **Scope:** "simplify the last commit" / "simplify staged" / "simplify

src/foo.py" → narrow the diff source accordingly (see Phase 1).

Do NOT auto-run this after every edit. It costs three subagents' worth of tokens — invoke it only when the user explicitly asks.

The Process

Phase 1 — Identify the changes

Capture the diff to review. Pick the source by what the user asked for, in this default order:

# 1. Default: uncommitted working-tree changes (tracked files)
git diff

# 2. If that's empty, include staged changes
git diff HEAD

# 3. Scoped variants the user may request:
git diff --staged                 # "staged changes"
git diff HEAD~1                    # "the last commit"
git diff main...HEAD              # "this branch" / "my PR"
git diff -- src/foo.py            # specific file(s)

If `git diff` and `git diff HEAD` are both empty and there's no git repo or no changes, fall back to the files the user explicitly named or that were recently created/edited in this session. If you genuinely can't find any changed code, say so and stop — there's nothing to simplify.

Capture the full diff text. Note its size: if it's very large (say >2000 changed lines), warn the user that three subagents each carrying the full diff will be token-heavy, and offer to scope it down (per-directory, per-commit) before proceeding.

Phase 2 — Launch three reviewers in parallel

Use `delegate_task` **batch mode** — pass all three tasks in one `tasks` array so they run concurrently. Three is the right fan-out for this pattern; it's well within the `delegation.max_concurrent_children` budget on any default install.

Give **every** reviewer the **complete diff** (not fragments — cross-file issues hide in the gaps) plus the absolute repo path so they can search the wider codebase. Each reviewer gets `terminal`, `file`, and `search` toolsets (so they can `git`, `read_file`, and `search_files`/grep).

Tell each reviewer to:

• Search the existing codebase for evidence (don't reason from the diff alone).
• **Apply Chesterton's Fence:** before flagging anything for removal, run

`git blame` on the line to understand why it exists. If you can't determine the original purpose, mark it `confidence: low` — don't guess.

• Report findings as structured output with confidence and risk:

  file:line → problem → suggested fix | confidence: high/medium/low | risk: SAFE/CAREFUL/RISKY

• **SAFE** = proven not to affect behavior (unused imports, commented-out

code, pass-through wrappers). Auto-apply these.

• **CAREFUL** = improves without changing semantics (rename local variable,

flatten nested ternary, extract helper). Apply with test verification.

• **RISKY** = may change behavior or breaks public contracts (N+1

restructuring, public API rename, memory lifecycle change). Flag for human review — do NOT auto-apply.

• Skip nits and style-only churn. Only flag things that materially improve

the code.

Pass these three goals (drop any the user's focus excludes):

**Reviewer 1 — Code Reuse** > Review this diff for code that duplicates functionality already in the > codebase. Search utility modules, shared helpers, and adjacent files > (use search_files / grep) for existing functions, constants, or patterns > the new code could call instead of reimplementing. Flag: new functions > that duplicate existing ones; hand-rolled logic that an existing utility > already does (manual string/path manipulation, custom env checks, ad-hoc > type guards, re-implemented parsing). For each, name the existing thing to > use and where it lives.

**Reviewer 2 — Code Quality** > Review this diff for quality problems. Look for: redundant state (values > that duplicate or could be derived from existing state; caches that don't > need to exist); parameter sprawl (new params bolted on where the function > should have been restructured); copy-paste-with-variation (near-duplicate > blocks that should share an abstraction); leaky abstractions (exposing > internals, breaking an existing encapsulation boundary); stringly-typed > code (raw strings where a constant/enum/registry already exists — check the > canonical registries before flagging); AI-generated slop patterns (extra > comments restating obvious code like `// increment counter` above `count++`; > unnecessary defensive null-checks on already-validated inputs; `as any` > casts that bypass the type system; patterns inconsistent with the rest of > the file)