Spec Review

spec-review — did we build what the PRD asked, the way the contract says?

Two-axis review of the diff between HEAD and a fixed point:

• Spec — does the change faithfully implement what .workflow/PRD.md / tasks.md asked for?
• Standards — does it obey the contract this project was built under?

Both run as parallel sub-agents so neither pollutes the other's context, then this skill reports them side by side.

Credit. The two-axis structure, the parallel-sub-agent split, the refusal to merge verdicts and the Fowler smell baseline are adapted from Matt Pocock's code-review skill (mattpocock/skills, MIT — the skill now lives at docs/engineering/code-review.md; both paths checked 2026-08-26) and the essay behind it. What's ours is the half his skill has to search for: in a dev-flow project the spec and the standards are at known paths.

Why this is not /code-review

Claude Code ships a built-in /code-review, and Pocock's own write-up lists the name collision as a known problem. This skill is deliberately not that, in name or in remit:

Run both if you like — they don't overlap. Without a .workflow/, this skill refuses and points at the built-in: with no spec and no declared stack, both of its axes are guesswork.

Workflow

1. Pin the fixed point — and fail here, not inside a sub-agent

Whatever the user names is the fixed point (a SHA, main, a tag, HEAD~5). If they didn't say, ask.

git rev-parse <fixed-point>                    # must resolve
git diff <fixed-point>...HEAD --stat           # three-dot: compare against the merge-base
git log  <fixed-point>..HEAD --oneline         # the commits under review

A bad ref or an empty diff must fail right here — discovering it inside two parallel sub-agents wastes both. Three dots, not two: you want the merge-base, not everything that landed on main meanwhile. And the diff excludes uncommitted work, so commit (or stash) before asking for a review, or the change you most want looked at is the one nobody sees.

2. Resolve the Spec axis — deterministic, not a search

This is where the contract earns its keep. In order:

1. .workflow/tasks.md — the tasks this branch claims to close. Match by branch name, by the task ids in the commit messages, or ask which ones are in scope.
2. .workflow/PRD.md — the requirement behind those tasks; the tasks are the decomposition, the PRD is the intent. A diff can satisfy every task and still miss what the PRD asked for.
3. meta.json#artifacts — what was produced and by which skill, so the reviewer knows whether a file is hand-written or generated (holding generated scaffolding to hand-written standards is noise).
4. linear-scrum projects — the issue in Linear is the live spec; meta.json#linear has the link.

If .workflow/PRD.md is absent (a project adopted mid-flight), say so and run the Spec axis against tasks.md alone, or skip it and report that the axis was not run — never invent the spec from the diff. A review that infers the requirements from the code it is reviewing always passes.

3. Resolve the Standards axis — the contract first, Fowler as the floor

A dev-flow project's documented standards are not a CONTRIBUTING.md someone may have written. They are:

Skip anything tooling already enforces. biome/eslint, tsc, and the three gates (shadscan, vercel-doctor, compliance-audit) have their own runs; repeating them here produces a long report that says nothing new. If the project has a lint gate, a review finding about formatting is noise.

The smell baseline — twelve smells, selected (Fowler, Refactoring 2nd ed., ch. 3)

The chapter catalogues more than these; the twelve below are the ones that show up in a diff, which is all this skill ever sees. Each is a labelled heuristic — "possible Feature Envy" — never a hard violation, and any documented standard above overrides it.

• Mysterious Name — a name that doesn't reveal what it does or holds. → rename; if no honest name comes, the design is murky.
• Duplicated Code — the same logic shape in more than one hunk. → extract, call from both.
• Feature Envy — a method reaching into another object's data more than its own. → move it onto the data it envies.
• Data Clumps — the same few params always travelling together. → one type, passed once.
• Primitive Obsession — a string or number standing in for a domain concept. → give the concept its own small type.
• Repeated Switches — the same cascade on the same type recurring. → polymorphism, or one shared map.
• Shotgun Surgery — one logical change forcing scattered edits. → gather what changes together.
• Divergent Change — one module edited for several unrelated reasons. → split it.
• Speculative Generality — abstraction for needs the spec doesn't have. → delete it. (This one pairs with the Spec axis: it is usually scope creep wearing a design hat.)
• Message Chains — long a.b().c().d() the caller shouldn't depend on. → hide the walk.
• Middle Man — a unit that mostly delegates onward. → cut it.
• Refused Bequest — a subclass ignoring most of what it inherits. → composition instead.

4. Spawn both sub-agents, in parallel, and forbid further delegation

Each gets the diff command, the commit list, its own sources pasted in full (a sub-agent has no access to what you read), and an explicit "do not spawn further agents" — Pocock's write-up records recursive spawning as a real failure mode when the brief doesn't forbid it.

Spec brief — "Report: (a) requirements the spec asked for that are missing or partial; (b) behaviour in the diff nobody asked for (scope creep); (c) requirements that look implemented but where the implementation looks wrong. Quote the PRD or task line for each finding. Under 400 words."

Standards brief — "Report, per file/hunk: (a) every place the diff breaks a documented standard — cite it (which rule, which file); (b) any baseline smell — name it and quote the hunk. Documented breaches can be hard findings; baseline smells are always judgement calls; a documented standard overrides the baseline. Skip anything lint/tsc/the gates enforce. Under 400 words."

5. Report side by side — and do not merge

Present under ## Spec and ## Standards, verbatim or lightly cleaned. Never merge or re-rank across axes. Close with the count per axis and the worst issue within each.

That separation is the whole point: a change can follow every convention and implement the wrong feature (Standards pass, Spec fail), or do exactly what the PRD asked while ignoring the stack the project declared (Spec pass, Standards fail). One combined verdict lets either hide behind the other.

Findings are hypotheses. Verify before acting. This repo's own [VERIFY] discipline exists for the same reason, and the 2026-08-26 sweep proved the point: of ~55 markers closed across the skill set, a handful turned out to be confidently wrong rather than merely unchecked — a removed module path still documented as current, a dead source-of-truth link, a package namespace that does not exist, an upstream issue described as open that had been closed won't fix. A report that reads well is not a report that is right.

meta.json#spec_review block

"spec_review": {
  "last_run_at": "<ISO>",
  "fixed_point": "main",              // what HEAD was compared against
  "commits": 7,
  "spec_sources": ["tasks.md#T12-T15", "PRD.md#3.2"],
  "spec_findings": { "missing": 1, "scope_creep": 2, "wrong": 0 },
  "standards_findings": { "hard": 1, "judgement": 4 },
  "axes_not_run": []                  // e.g. ["spec"] when there is no PRD — say so, never infer it
}

dev-flow hook

Horizontal capability — run it on any diff. dev-flow proposes it when a chunk of work lands (page_generated, module_added) rather than only before shipping: a spec finding is cheapest while the branch is still open. It is not a fourth pre-deploy gate — compliance-audit, vercel-doctor and shadscan read the finished artefact, this reads the change. Records meta.json#spec_review + history; never bumps phase; never blocks anything.

What this skill does NOT do

• Not generic code review — no .workflow/, no run; use the built-in /code-review.
• Doesn't run tests, lint or typecheck — it reads their results and skips what they cover.
• Doesn't fix anything. It reports. Fixes go to the owning skill (forms, data-fetching, …).
• Doesn't merge the two axes, and doesn't pick a winner between them.

Reference files

• references/contracts.md — the .workflow/ dev-flow contract (vendored).

Sources

• https://www.aihero.dev/skills-code-review · mattpocock/skills (MIT) — the two-axis structure and the smell baseline. Both 200 on 2026-08-26; upstream has since moved its skills under docs/engineering/, where code-review.md still lives.
• Fowler, Refactoring (2nd ed.), ch. 3 — the smell catalogue.