| name | dev-ponytail-review |
| description | Review a diff or branch for over-engineering only — reinvented stdlib, dependencies the platform covers, one-implementation abstractions, dead flexibility, code that shrinks. Use on "review for over-engineering", "is this over-engineered", "what can we delete", "simplify review". Correctness, security, and performance stay with `dev-code-review`. |
Review the diff for unnecessary complexity, nothing else. Its best outcome is
getting shorter.
Delivery Mode (lite | full | ultra, default lite)
Mode is the trailing argument when it is exactly lite, full, or ultra; everything else is the task/feature description. No mode given → lite.
lite (default) — the five biggest cuts. Report only.full — every finding, ranked biggest cut first. Report only.ultra — full, then apply the unambiguous findings (a stdlib swap, a one-implementation interface inlined) and leave them uncommitted. Judgement calls stay findings.
Scope
Named target → review it. Otherwise the working diff (git diff + staged), and
if that's empty, the branch against its merge base.
Read the surrounding code, not just the hunks: "this abstraction has one
implementation" is a claim about the whole repo, and a wrong finding costs more
than a missed one.
Format
<file>:L<line>: <tag> <what>. <replacement>. — L<line>: alone for a
single-file diff.
delete: dead code, unused flexibility, speculative feature. Replacement: nothing.stdlib: hand-rolled thing the stdlib ships. Name the function.native: dependency or code doing what the platform does. Name the feature.yagni: abstraction with one implementation, config nobody sets, layer with one caller.shrink: same logic, fewer lines. Show the shorter form.
Not a hedged paragraph — "this EmailValidator might be more complex than
necessary, have you considered..." — but:
L12-38: stdlib: 27-line validator class. "@" in email; the confirmation mail is the real validation.L4: native: moment.js for one format call. Intl.DateTimeFormat, zero deps.repo.py:L88: yagni: AbstractRepository with one implementation. Inline until a second exists.L52-71: delete: retry wrapper around an idempotent local call. Nothing replaces it.L30-44: shrink: manual loop builds a dict. dict(zip(keys, values)), one line.
End with net: -<N> lines possible. (deleted minus what replacements add).
Nothing to cut → Lean already. Ship. A tight diff is a pass, not a failed hunt.
Boundaries
Complexity only. A real bug spotted while reading gets one line at the end under
out of scope: and goes to dev-code-review — don't swallow it, don't expand
into a full review.
One smoke test or assert self-check is the dev-ponytail minimum, not bloat.
Never flag it for deletion.
