Simplify

Simplify: Code Review and Cleanup

Review all changed files for reuse, quality, and efficiency. Fix any issues found.

Subagents

This skill uses the cexplore subagent and launches three parallel review subagents for code analysis.

Phase 1: Understand Context and Identify Changes

1. Read docs/plans/.latest to get the plan path, then read the plan document. This tells you what was implemented, which files were touched, and the intent behind the changes.
2. Run git diff (or git diff HEAD if there are staged changes) to see the actual code changes. Use the plan as a map — it tells you what each change is supposed to accomplish.
3. Read the changed files fully so you understand the surrounding code, not just the diff hunks.

Phase 2: Launch Three Review Agents in Parallel

Use the runSubAgent tool to launch all three agents concurrently in a single message. Pass each agent the full diff so it has the complete context.

Agent 1: Code Reuse Review

For each change:

1. Search for existing utilities and helpers that could replace newly written code. Use search to find similar patterns elsewhere in the codebase — common locations are utility directories, shared modules, and files adjacent to the changed ones.
2. Flag any new function that duplicates existing functionality. Suggest the existing function to use instead.
3. Flag any inline logic that could use an existing utility — hand-rolled string manipulation, manual path handling, custom environment checks, ad-hoc type guards, and similar patterns are common candidates.

Agent 2: Code Quality Review

Review the same changes for hacky patterns:

1. Redundant state: state that duplicates existing state, cached values that could be derived, observers/effects that could be direct calls
2. Parameter sprawl: adding new parameters to a function instead of generalizing or restructuring existing ones
3. Copy-paste with slight variation: near-duplicate code blocks that should be unified with a shared abstraction
4. Leaky abstractions: exposing internal details that should be encapsulated, or breaking existing abstraction boundaries
5. Stringly-typed code: using raw strings where constants, enums (string unions), or branded types already exist in the codebase

Agent 3: Efficiency Review

Review the same changes for efficiency:

1. Unnecessary work: redundant computations, repeated file reads, duplicate network/API calls, N+1 patterns
2. Missed concurrency: independent operations run sequentially when they could run in parallel
3. Hot-path bloat: new blocking work added to startup or per-request/per-render hot paths
4. Unnecessary existence checks: pre-checking file/resource existence before operating (TOCTOU anti-pattern) — operate directly and handle the error
5. Memory: unbounded data structures, missing cleanup, event listener leaks
6. Overly broad operations: reading entire files when only a portion is needed, loading all items when filtering for one

Phase 3: Fix Issues

Wait for all three agents to complete. Aggregate their findings and fix each issue directly. If a finding is a false positive or not worth addressing, note it and move on — do not argue with the finding, just skip it.

After fixing, commit the cleanup as a single commit: refactor: simplify and clean up implementation

Phase 4: Handover

When done, briefly summarize what was fixed (or confirm the code was already clean).

Use #askQuestions to ask what the user wants to do next:

After the user picks a next skill, announce the handover and load the chosen skill.