pharaoh-arch-review

name	pharaoh-arch-review
description	Use when auditing a single architecture element against the 10 ISO 26262-8 §6 axes plus arch-specific axes (traceability back to requirement). Emits structured findings JSON.
chains_from	["pharaoh-arch-draft"]
chains_to	["pharaoh-req-regenerate"]

pharaoh-arch-review

When to use

Invoke when the user has a single architecture element (either just drafted by pharaoh-arch-draft or retrieved from needs.json by ID) and wants per-axis inspection against ISO 26262-8 §6.

Do NOT review sets of arch elements — each invocation audits exactly one element. Do NOT re-author or fix — emit findings only. Re-authoring is a follow-up step outside this skill's scope. Do NOT audit requirements — use pharaoh-req-review for those.

---

Inputs

• target: either an RST directive block (from pharaoh-arch-draft) OR a need-id present in needs.json
• tailoring (from .pharaoh/project/):
  • artefact-catalog.yaml — arch entry; required/optional fields
  • id-conventions.yaml — id_regex and prefix map
• needs.json: required for traceability axis (verifying :satisfies: resolves to a req)

---

Outputs

A single JSON document with no prose wrapper. Shape mirrors pharaoh-req-review, with traceability added as a binary axis and verifiability adapted for arch context:

{
  "need_id": "arch__example",
  "axes": {
    "atomicity":              {"score": 0, "reason": "..."},
    "internal_consistency":   {"score": 0, "reason": "..."},
    "traceability":           {"score": 0, "reason": "..."},
    "completeness":           {"score": "deferred", "reason": "set-level axis — see note"},
    "external_consistency":   {"score": "deferred", "reason": "set-level axis — see note"},
    "no_duplication":         {"score": "deferred", "reason": "set-level axis — see note"},
    "schema":                 {"score": 0, "reason": "..."},
    "maintainability":        {"score": null, "reason": "chain-level axis — see note"},
    "unambiguity_prose":      {"score": 0, "reason": "..."},
    "comprehensibility":      {"score": 0, "reason": "..."},
    "feasibility":            {"score": 0, "reason": "..."}
  },
  "action_items": ["..."],
  "overall": "pass"
}

Note: verifiability from req-review is replaced by traceability for arch elements. Architecture elements are not directly tested; they must trace to a requirement that carries the verification link.

Score scales

Binary (0 or 1) — mechanized axes:

Axis	Score 0 = FAIL	Score 1 = PASS
atomicity	element bundles more than one distinct architectural concern (e.g. two independent responsibilities in the body)	element represents exactly one coherent architectural unit
internal_consistency	body contains a self-contradictory statement	no self-contradiction detectable within this element
traceability	:satisfies: field absent, empty, or the linked ID does not exist in needs.json as a requirement type	:satisfies: present and resolves to a requirement-type need in needs.json
schema	any field listed in required_fields for the arch entry in artefact-catalog.yaml is missing	all required fields present and non-empty

Ordinal (0–3) — subjective LLM-judge axes:

Axis	0	1	2	3
unambiguity_prose	multiple conflicting interpretations of the element's responsibility	single interpretation but phrasing is awkward	single clear interpretation; minor phrasing issues	unambiguous and precise
comprehensibility	adjacent-level reader (test engineer or architect) cannot follow	mostly unclear without extra context	mostly clear; minor jargon	fully self-contained and clear
feasibility	obviously unrealisable given item-development constraints	realisable but significant unknowns	realisable with known engineering effort	clearly realisable; well-bounded

Deferred set-level axes

completeness, external_consistency, and no_duplication require the full set of sibling architecture elements. Defer to a planned pharaoh-arch-set-review skill.

In the output JSON, record each as {"score": "deferred", "reason": "set-level axis — assess with pharaoh-arch-set-review"}.

Chain-level axis

maintainability requires observing convergence across regeneration iterations. Record as {"score": null, "reason": "chain-level axis — assess after the parent requirement and architecture revisions land"}.

overall field

Computed from non-deferred, non-null axes (atomicity, internal_consistency, traceability, schema, unambiguity_prose, comprehensibility, feasibility):

• "pass" — all binary axes score 1, all subjective axes score ≥ 2
• "needs_work" — no binary axis fails, but ≥ 1 subjective axis scores < 2
• "fail" — ≥ 1 binary axis scores 0

---

Process

Step 1: Read tailoring

Read .pharaoh/project/artefact-catalog.yaml and .pharaoh/project/id-conventions.yaml.

For the arch artefact type, extract:

• required_fields (expected: [id, status, satisfies, type])
• id_regex

If the arch entry is absent from artefact-catalog, apply defaults:

• required_fields: [id, status, satisfies, type] Note the fallback in output.

---

Step 2: Resolve target

If target is a need-id:

1. Find needs.json (docs/_build/needs/needs.json, then _build/needs/needs.json).
2. Look up the need-id in the needs map.
3. If not found, FAIL (see Guardrails G1).
4. Extract title, all option fields, and body text.

If target is an RST directive block:

1. Parse the block — extract :id:, :status:, :satisfies:, :type:, and body.
2. Determine artefact type from the directive name (e.g. .. arch:: → type arch).
3. If needs.json is available, check whether the ID already exists (may be a re-review).

---

Step 3: Evaluate binary axes

Atomicity:

Read the body. Assess whether it describes a single coherent architectural concern or bundles multiple independent responsibilities. Look for:

• Multiple distinct systems or subsystems described as owned by this element
• Compound responsibility lists joined by "and" describing unrelated concerns

Score 1 if the body describes one coherent unit. Score 0 if two or more clearly separable responsibilities are described.

Internal consistency:

Read the body for contradictory statements (e.g. "is responsible for X" followed by "does not handle X"). Score 1 if no contradiction; score 0 if one is identifiable.

Traceability:

Check :satisfies: option:

1. Present and non-empty — if absent, score 0.
2. Resolves in needs.json — if the ID does not exist, score 0.
3. The resolved need is a requirement type (prefix ends in req or equivalent) — if it is a non-requirement type (e.g. wf, wp), score 0 and note the type mismatch.

Score 1 only if all three conditions hold.

Schema:

Verify every field in required_fields is present and non-empty. For default arch: id, status, satisfies, type must all be present. Score 0 with reason listing missing field(s) if any are absent.

---

Step 4: Evaluate subjective axes

Unambiguity (prose):

Read the body. Assess whether a reader can derive only one interpretation of the element's responsibility. Vague ownership ("may handle", "is sometimes responsible for") → score 1. Clear, bounded description → score 3.

Comprehensibility:

Assess whether a test engineer or software architect at an adjacent level could understand what this element does without reading any other document. Check for undefined acronyms, missing subject, and missing context. Full clarity → score 3; requires significant additional context → score 0.

Feasibility:

Assess whether the element as described could be realised within typical automotive software item-development constraints. Flag obviously infeasible claims (score 0), heavily under-constrained elements (score 1), normal engineering effort (score 2), or tightly and clearly bounded elements (score 3).

---

Step 5: Record deferred and null axes

Set completeness, external_consistency, no_duplication to {"score": "deferred", "reason": "set-level axis — assess with pharaoh-arch-set-review"} and maintainability to {"score": null, "reason": "chain-level axis — assess after the parent requirement and architecture revisions land"}.

---

Step 6: Compute overall and action items

Compute overall from non-deferred, non-null axes per the policy above.

For each binary axis scoring 0 and each subjective axis scoring 0 or 1, add a concrete action item naming the axis and stating what must change.

If all 7 evaluated axes pass/score ≥ 2, action_items is an empty array.

---

Step 7: Emit JSON

Emit only the JSON document. Do not prepend or append prose.

---

Guardrails

G1 — Unresolved target

If target is a need-id and it does not appear in needs.json:

FAIL: need-id "<id>" not found in needs.json.
Verify the ID is correct or build the Sphinx project first.

G2 — Malformed JSON output

If the emitted JSON is syntactically invalid or missing any axis key, self-correct once. If still malformed after one correction attempt:

{
  "need_id": "<id>",
  "diagnostic": "JSON self-correction failed. Raw findings follow.",
  "raw": "<free-text findings>"
}

G3 — Insufficient context for subjective axis

If the element body is empty or too short to assess a subjective axis, record: {"score": 0, "reason": "insufficient context — body is empty or too short to assess"}. Continue evaluating remaining axes.

---

Advisory chain

If overall is "needs_work" or "fail", append — after the JSON — a single line:

Re-run this review after action items are addressed to confirm the findings are resolved.

This is the only prose permitted after the JSON.

---

Worked example

Target (RST block from pharaoh-arch-draft):

.. arch:: ABS pump driver component
   :id: arch__abs_pump_driver
   :status: draft
   :satisfies: gd_req__abs_pump_activation
   :type: component

   The ABS pump driver component manages the pump drive circuit, controlling output
   PWM duty cycle and providing over-current protection for the pump motor.

Step 2: RST parsed. needs.json found; gd_req__abs_pump_activation resolves as type gd_req.

Step 3 — binary axes:

• atomicity: body describes one coherent unit (pump drive circuit management); no separate unrelated concerns → score 1
• internal_consistency: no self-contradiction → score 1
• traceability: :satisfies: gd_req__abs_pump_activation present; resolves in needs.json; type is gd_req → score 1
• schema: id, status, satisfies, type all present → score 1

Step 4 — subjective axes:

• unambiguity_prose: single clear interpretation (manages pump drive circuit) → score 3
• comprehensibility: subject, responsibility, and constraints explicit; no undefined acronyms (PWM is standard automotive abbreviation) → score 3
• feasibility: standard automotive power electronics function; well-constrained → score 3

Step 6: all 7 evaluated axes pass or score ≥ 2 → overall = "pass", action_items = [].

Step 7 output:

{
  "need_id": "arch__abs_pump_driver",
  "axes": {
    "atomicity":            {"score": 1, "reason": "single coherent unit: pump drive circuit management"},
    "internal_consistency": {"score": 1, "reason": "no self-contradictory statement detected"},
    "traceability":         {"score": 1, "reason": ":satisfies: gd_req__abs_pump_activation resolves as type gd_req"},
    "schema":               {"score": 1, "reason": "id, status, satisfies, type all present"},
    "completeness":         {"score": "deferred", "reason": "set-level axis — assess with pharaoh-arch-set-review"},
    "external_consistency": {"score": "deferred", "reason": "set-level axis — assess with pharaoh-arch-set-review"},
    "no_duplication":       {"score": "deferred", "reason": "set-level axis — assess with pharaoh-arch-set-review"},
    "maintainability":      {"score": null, "reason": "chain-level axis — assess after the parent requirement and architecture revisions land"},
    "unambiguity_prose":    {"score": 3, "reason": "single clear interpretation: manages pump drive circuit"},
    "comprehensibility":    {"score": 3, "reason": "subject, responsibility, and constraints all explicit"},
    "feasibility":          {"score": 3, "reason": "standard automotive power electronics function; well-constrained"}
  },
  "action_items": [],
  "overall": "pass"
}