Independent review

Spec 004 promoted this skill from stub to active. The prompt is constructed by review.py; Claude owns the Task invocation.

What this skill does

Constructs the standardized reviewer-subagent prompt and tells Claude when / how to spawn the Task. The skill has four modes, matching the review passes every slice may run:

• Implementation review — after the implementer writes the deliverable to disk. The reviewer evaluates each acceptance criterion against the actual files; returns pass | fail | needs-changes. This is the compliance pass in spec-workflow's multi-pass flow.
• Pr-review (craft pass) — slice 031-01. After the compliance pass returns, the orchestrator runs a craft-pass review that produces the four-bucket output (scope / blockers / nits / strengths) the jig:pr-review skill emits, wrapped in the same verdict envelope as the compliance pass. SPECIFIC ISSUES entries are tagged [blocker] / [nit] / [strength] so the workflow can decide what blocks the REVIEWED transition vs. what becomes a reconciliation-log entry.
• Arch-review (architecture pass — on-demand) — slice 031-02. After the craft pass returns, the orchestrator queries the slice's arch_review: frontmatter flag via workflow.py arch-review-needed; when true, it runs an arch pass producing the four-bucket output (summary / strengths / concerns / open questions) the jig:arch-review skill emits, in the same verdict envelope. Slice authors set arch_review: true in the slice's frontmatter when the slice changes module boundaries, public contracts, or architecture-shaped concerns; the slice template at templates/docs/specs/slice-template.md ships the field commented out as a discoverability nudge.
• Design-review (attest-only pass — on-demand) — slice 071-01 / ADR-0022. After the craft (+ arch) passes, the orchestrator queries the slice's design_review: flag via workflow.py design-review-needed; when true, it runs an attest-only pass: the read-only reviewer attests an external, non-deterministic design-fidelity eval's frozen verdict (e.g. servo's .servo/design-eval/ composite ≥ its own threshold, non-stale, env_error ≠ pass) and records pass/fail — it never re-runs or re-derives the score (servo runs/scores, jig attests). Gates REVIEWED like arch. Authors set design_review: true when the slice ships UI gated by an external design-fidelity eval — and the slice body must point at where the eval evidence lives (the frozen config + threshold and the results ledger), since the reviewer can only attest a verdict it can locate; with no pointer it has nothing to read and records a fail.
• Reconciliation review — after the deviation log is written. The reviewer verifies the doc changes match reality; does NOT re-review the ACs.

review.py builds the prompt text; agents/reviewer.md defines the agent's tool restrictions and persistent system rules.

How to use

Task telemetry tags

When you feed a review.py prompt to the Task tool, prefix the prompt with the compact attribution tags that jig-telemetry.sh records:

[jig:phase=<phase>] [jig:spec=NNN] [jig:slice=NNN-NN]

<review.py prompt body>

Use compliance for review.py implementation, craft for pr-review, arch for arch-review, code-health for code-health, frame-critique for frame critique, and reconciliation for reconciliation review. These tags make later token reports price the workflow phase, not just the subagent type.

Implementation review

After the implementer has written the deliverable to disk:

PROMPT=$(python3 "${CLAUDE_PLUGIN_ROOT}/skills/independent-review/review.py" \
  implementation \
  "docs/specs/NNN-<slug>/spec.md" \
  "<slice-fragment>" \
  "<deliverable-path-1>" "<deliverable-path-2>" ...)
SUBAGENT=$(python3 "${CLAUDE_PLUGIN_ROOT}/skills/independent-review/review.py" \
  subagent-type implementation)

Then feed [jig:phase=compliance] [jig:spec=NNN] [jig:slice=NNN-NN]\n\n$PROMPT to the Task tool with subagent_type: "$SUBAGENT". The helper resolves $SUBAGENT deterministically — reviewer when jig is installed as a plugin (the real filesystem-based agent is reachable), general-purpose when running from source. Wait for the verdict. Address any fail/needs-changes findings; rerun the helper + Task as needed until pass.

Pr-review (craft pass — slice 031-01)

After the compliance pass returns pass, run the craft pass:

PROMPT=$(python3 "${CLAUDE_PLUGIN_ROOT}/skills/independent-review/review.py" \
  pr-review \
  "docs/specs/NNN-<slug>/spec.md" \
  "<slice-fragment>" \
  "<deliverable-path-1>" "<deliverable-path-2>" ...)
SUBAGENT=$(python3 "${CLAUDE_PLUGIN_ROOT}/skills/independent-review/review.py" \
  subagent-type pr-review)

Feed [jig:phase=craft] [jig:spec=NNN] [jig:slice=NNN-NN]\n\n$PROMPT to Task with subagent_type: "$SUBAGENT". The prompt points the reviewer at the most-specific pr-review SKILL.md reachable in the environment — Claude's skill router resolves user > project > jig:pr-review precedence via the skill description hints. The pass returns the canonical four output buckets (scope / blockers / nits / strengths) wrapped in the same verdict envelope as the compliance pass. SPECIFIC ISSUES entries are tagged [blocker] / [nit] / [strength]; only [blocker] entries block the REVIEWED transition.

Arch-review (architecture pass — slice 031-02, on-demand)

The arch pass runs only when the slice's frontmatter declares arch_review: true. Query the flag via workflow.py arch-review-needed before spawning:

# Capture the helper exit code — a non-zero exit means the slice lookup
# failed, not "no arch pass needed." Surface the error rather than
# silently skipping the pass.
if ! NEED_ARCH=$(python3 "${CLAUDE_PLUGIN_ROOT}/skills/spec-workflow/workflow.py" \
    arch-review-needed \
    "docs/specs/NNN-<slug>/spec.md" \
    "<slice-fragment>"); then
  echo "arch-review-needed failed — aborting" >&2
  exit 2
fi
if [ "$NEED_ARCH" = "true" ]; then
  PROMPT=$(python3 "${CLAUDE_PLUGIN_ROOT}/skills/independent-review/review.py" \
    arch-review \
    "docs/specs/NNN-<slug>/spec.md" \
    "<slice-fragment>" \
    "<deliverable-path-1>" "<deliverable-path-2>" ...)
  SUBAGENT=$(python3 "${CLAUDE_PLUGIN_ROOT}/skills/independent-review/review.py" \
    subagent-type arch-review)
fi

When $NEED_ARCH is true, feed [jig:phase=arch] [jig:spec=NNN] [jig:slice=NNN-NN]\n\n$PROMPT to Task with subagent_type: "$SUBAGENT". The prompt routes via the same prose-based dispatch as pr-review to the most-specific arch-review SKILL.md reachable. The pass returns the canonical four arch output buckets (summary / strengths / concerns / open questions). Tag and block semantics match the craft pass: [blocker] entries block the REVIEWED transition; [nit] entries and needs-changes become reconciliation-log items.

Slice authors set arch_review: true in the slice file's frontmatter when the slice changes module boundaries, public contracts, or architecture-shaped concerns. The slice template ships the field commented out as a discoverability nudge.

Frame-critique (adversarial pass — slice 064-03 / ADR-0020, on-demand)

Unlike every other pass, frame-critique runs PRE-implementation — it gates the DRAFT → READY_FOR_REVIEW transition of a spec/slice (or, once 064-05 lands, an ADR at adr.py accept), before any code exists. Its job is adversarial, not conformance: a fresh reviewer hunts the single load-bearing assumption most likely to be wrong and argues why, so a bad premise is caught at authoring time (the cheapest point) rather than executed with discipline. It runs only when the artifact declares a truthy frame_review flag.

PROMPT=$(python3 "${CLAUDE_PLUGIN_ROOT}/skills/independent-review/review.py" \
  frame-critique \
  "docs/specs/NNN-<slug>/spec.md" \
  "<slice-fragment>" \
  "<deliverable-path>" ...)
SUBAGENT=$(python3 "${CLAUDE_PLUGIN_ROOT}/skills/independent-review/review.py" \
  subagent-type)

Feed [jig:phase=frame-critique] [jig:spec=NNN] [jig:slice=NNN-NN]\n\n$PROMPT to Task with subagent_type: "$SUBAGENT".

Record the verdict as the frame-critique pass (below); the READY_FOR_REVIEW gate requires it iff frame_review is truthy (default-off artifacts transition freely). Model policy (ADR-0020): run frame-critique equal-or-stronger than the artifact's author — never downgrade it for cost (the one pass whose value is adversarial depth). 064-03 ships rung-1 (fresh-context subagent) independence; cross-model (rung-3) is deferred (docs/refinement-todo.md).

Design-review (attest-only pass — slice 071-01 / ADR-0022, on-demand)

Unlike every other pass, design-review produces no judgment of its own — it attests an external, non-deterministic eval's frozen verdict. The eval (e.g. servo's design-fidelity oracle) is the thing that RUNS the UI and SCORES it against a frozen design definition; this pass's read-only reviewer confirms, by reading the recorded eval evidence, that the eval actually RAN, is NON-STALE (its frozen config/threshold unchanged since the run), is HONEST (an env_error / infra failure is not a pass and not a 0.0), and that the latest composite is ≥ the eval's own declared threshold — then RECORDS that verdict. It never re-runs, re-derives, or re-judges the score: servo runs and scores, jig attests (the ADR-0022 honesty boundary). It runs only when the slice declares a truthy design_review flag, and gates REVIEWED exactly like arch.

PROMPT=$(python3 "${CLAUDE_PLUGIN_ROOT}/skills/independent-review/review.py" \
  design-review \
  "docs/specs/NNN-<slug>/spec.md" \
  "<slice-fragment>" \
  "<deliverable-path>" ...)

Record the verdict as the design-review pass; the REVIEWED gate requires it iff design_review is truthy (default-off slices transition freely). Although the shared envelope offers pass | fail | needs-changes, an attestation is binary — the recorded eval verdict either attests (honest, non-stale, meets its threshold) or it does not — so this pass meaningfully emits only pass / fail (the gate clears on pass and blocks on either of the others). No richer-skill detection — there is no external "design-review" skill category; the pass attests jig's own eval evidence. First consumer: food-log slice 002-01 (servo design-fidelity eval).

The design_review flag is set by hand on a slice/spec whose deliverable is validated by an external design-fidelity eval — there is no mechanical derivation (unlike frame_review, which slice 064-04 derives from the spec's grounding). Once set, workflow.py session-plan surfaces the pass on the dispatch plan so it isn't a dead loop.

Reconciliation review

After the deviation log subsection has been added under the slice in spec.md:

PROMPT=$(python3 "${CLAUDE_PLUGIN_ROOT}/skills/independent-review/review.py" \
  reconciliation \
  "docs/specs/NNN-<slug>/spec.md" \
  "<slice-fragment>")
SUBAGENT=$(python3 "${CLAUDE_PLUGIN_ROOT}/skills/independent-review/review.py" \
  subagent-type reconciliation)

Feed [jig:phase=reconciliation] [jig:spec=NNN] [jig:slice=NNN-NN]\n\n$PROMPT to Task with subagent_type: "$SUBAGENT". The prompt explicitly tells the reviewer NOT to re-evaluate against ACs — it only verifies the deviation log matches reality.

Recording and checking review evidence (slice 045-02)

A review pass is durable evidence, not ephemeral chat. After a pass returns a verdict, record it as a file beside the slice it grades, at docs/specs/NNN-<slug>/reviews/slice-NN-<pass>.md (ADR-0014 §1). The schema (pass ∈ {compliance, craft, arch, code-health, frame-critique, reconciliation}, verdict ∈ {pass, fail, needs-changes}, plus reviewer, reviewed_at, prompt_source) lives in skills/_common/review_evidence.py so the slice 045-03 transition gate validates the same shape.

Record a verdict (the freeform body comes from --summary-file or stdin):

python3 "${CLAUDE_PLUGIN_ROOT}/skills/independent-review/review.py" \
  record-review \
  "docs/specs/NNN-<slug>/spec.md" \
  "<slice-fragment>" \
  --pass compliance \
  --verdict pass \
  --reviewer jig:reviewer \
  --prompt-source "review.py implementation ..." \
  --summary-file verdict.md

Re-recording the same (slice, pass) overwrites in place — git history is the audit trail, there is no append (ADR-0014 §4). A fail/needs-changes that has not been overwritten by a later pass therefore still blocks the gate, which is exactly the "superseded without a later pass" case.

Validate the evidence set for a slice at a transition stage:

python3 "${CLAUDE_PLUGIN_ROOT}/skills/independent-review/review.py" \
  check-reviews \
  "docs/specs/NNN-<slug>/spec.md" \
  "<slice-fragment>" \
  --stage REVIEWED   # or RECONCILED

check-reviews exits 0 when the required passes for the stage all clear (REVIEWED → compliance + craft, plus arch iff the slice declares arch_review: true; RECONCILED → reconciliation), or 2 with actionable diagnostics for missing files, malformed frontmatter, unknown pass/verdict values, non-clearing (superseded-only) verdicts, and invalid slice targets. The gate rule is uniform: a pass clears iff verdict: pass (ADR-0014 §3). Code-staleness (a pass artifact predating a later deliverable change) is deliberately NOT checked — it is a deferred enhancement (ADR-0014 Scope).

The full enforced flow. build prompt (review.py implementation / pr-review / arch-review) → spawn reviewer → record-review the verdict → check-reviews (optional preflight) → workflow.py transition … REVIEWED (or RECONCILED / DONE). The transition imports the same validator check-reviews uses, so the gate and this skill agree by construction. A refused transition names the missing/invalid artifact and the record-review command to produce it; a deliberate out-of-band flow bypasses the gate with JIG_REVIEW_EVIDENCE_GATE=0. Recovering from a failed review: address the findings, re-run the pass, record-review again (overwrites the earlier file for that (slice, pass) in place — git history is the audit trail), then re-run the transition; with every required pass now pass, the gate clears.

What gets put in the prompt automatically

• Standard preamble ("You are seeing this work for the first time")
• The slice's full label (helper looks it up from the spec)
• "What you must NOT do" block (no prior reasoning, no soften, no file writes, no docs/memory/ writes)
• Canonical output format (VERDICT | REASONING | SPECIFIC ISSUES | RECONCILIATION NOTES)

Context isolation pattern

Implementer writes deliverable to disk → review.py builds a self-contained prompt → Claude spawns the reviewer Task with that prompt → reviewer reads only what the prompt points at. This is imperfect (parent context is technically accessible to subagents — see GitHub issue #20304), but works reliably when the prompt is sharp.

Gotchas

• review.py does not spawn the Task. It only constructs the prompt string. Claude is responsible for invoking the Task tool with the prompt as the prompt parameter. This separation keeps review.py deterministic and testable.
• Reviewer agent is read-only by definition. agents/reviewer.md lists only Read, Glob, Grep in its tool set. No Write or Edit.
• Reviewer must not write to docs/memory/. Defining the glossary, capturing learnings, or modifying the hot cache is memory-sync's job, not the reviewer's.
• Reconciliation review never re-evaluates ACs. That's done. The reconciliation prompt explicitly states this so the reviewer doesn't drift into AC-re-review.
• Substring matching for slice fragments is identical to workflow.py — 001-01 matches ## Slice 001-01 — greenfield-scaffold. Ambiguous fragments are refused with exit 2.