simplify

A Skill that attempts to replicates the original bundled /simplify command that was removed in Claude Code v2.1.146. It's code review and cleanup on the changes you've made in your current branch.

What it does

Captures your current diff (git diff HEAD + untracked files), then runs three review subagents in parallel — each focused on a different dimension:

1. Code Reuse — missed opportunities to use existing helpers, hand-rolled logic that duplicates utilities elsewhere in the repo
2. Code Quality — redundant state, parameter sprawl, copy-paste, stringly-typed code, verbose patterns
3. Efficiency — unnecessary work, N+1 patterns, missed concurrency, hot-path bloat

Reviewers do not edit files. They return their findings as JSON. The main agent then merges everything, resolves overlaps deterministically using cross-cutting principles, and applies edits sequentially.

Principles (applied to every finding)

• Preserve behavior — a refactor that changes output on any input (even malformed input) is a redesign, not a simplification
• Clarity over brevity — fewer lines is not the goal; a reader grokking the code on first pass is
• Respect house conventions — CLAUDE.md rules win over generic idioms

When two reviewers propose different rewrites for the same region, the principles break the tie. When principles can't discriminate, neither is applied — both are logged under "Noticed but not applied" so you can opt in if you want one.

Why review-then-apply (and not edit-in-parallel)

If three subagents call Edit on the same files concurrently, they race. Late writers either fail loudly or — worse — silently skip when they see "my change is already there", dropping real findings. Parallelizing the slow part (analysis) while serializing writes gets both speed and correctness.

Install

Drop the skill into your global skills directory:

mkdir -p ~/.claude/skills/simplify
curl -fsSL https://raw.githubusercontent.com/gtapps/simplify/main/SKILL.md \
  -o ~/.claude/skills/simplify/SKILL.md

Or clone and copy:

git clone https://github.com/gtapps/simplify.git
cp simplify/SKILL.md ~/.claude/skills/simplify/SKILL.md

Then invoke with /simplify in any Claude Code session.

Usage

/simplify
/simplify memory efficiency
/simplify "avoid breaking the public API"

The optional argument is passed to all three reviewers as a focus hint — they'll weight that dimension when triaging findings.

Output

After applying, the skill prints a per-file summary plus a "Noticed but not applied" section and totals:

path/to/file.ts
  ✓ [Quality] removed `=== true` comparison on line 31
  ✓ [Reuse]   replaced manual loop with `.reduce(...)` on line 53
  ⊘ [Efficiency] skipped — old_string no longer matches (subsumed)

Noticed but not applied:
  ⚠ [Reuse] proposed `email.partition("@")` with None return for no-@ inputs
      (lines 95-99) — behavior change vs original (`""`). To apply: ask explicitly.

Totals: applied 2 · deduped 1 · principle-rejected 1 · stale-anchor skips 1 · parse failures 0

Cost / requirements

• Subagents are pinned to claude-sonnet-4-6 for predictable cost regardless of the parent session's model
• Typical run: 3 Sonnet calls (one per reviewer) plus the main-agent merge + apply pass
• For tiny diffs (<~20 lines, single concern), the skill skips Phase 2 and dispatches a single reviewer to avoid noise
• The skill is non-interactive — it never stops mid-run to ask. Rejected proposals end up in the report, not in a prompt

License

MIT — see LICENSE.