Ca Review Agent Skill

/ca-review — diff review

Read-only review of a change. Routes to dispatching-parallel-agents: dispatches the reviewer fleet by path matrix, dedupes, then funnels through finding-triage → checkpoint-aggregator to a single verdict. No code is modified.

The change under review does not have to be yours. /ca-review #123 reviews an inbound pull request through the same fleet, the same matrix, and the same triage. That is the point of issue #80: a tool that only reviews the diff you just wrote is a linter for authors, not a gate for a team, and reviewing code you did NOT write is where a governance gate earns its keep.

It is an ARGUMENT, not a second command. The scope resolver already took one, the fleet is scope-agnostic, and every phase downstream operates on a diff regardless of where it came from — so a /ca-review-pr would be a whole public surface (catalog, three host projections, README counts, sidebar) whose only distinguishing feature is where the diff was fetched from.

Flow

• Resolve scope from $ARGUMENTS:
• empty → the current working diff (unchanged default).
• a path → that path (unchanged).
• #<number>, a bare number, or a GitHub PR URL → an INBOUND PR. Fetch its diff with

gh pr diff <number> and review that. If gh is missing or unauthenticated, STOP and say so —

do NOT silently fall back to the working diff, which would report a verdict on the wrong change

under the PR's name.

For a PR target, resolve the diff ONCE and review that text. Do not re-fetch per reviewer: the

fleet runs in parallel, and a PR updated mid-review would otherwise have different reviewers

reading different code and a triage that reconciles findings from two versions.

• Build the unit list by path matrix; each matched reviewer is one read-only unit:

| Reviewer | Dispatched when scope touches |

|---|---|

| security-reviewer | auth, middleware, secrets, deploy/CI, any security-sensitive path |

| auth-crypto-reviewer | authn, crypto, key handling, secrets |

| dependency-reviewer | package.json, lockfiles, base images, dependency manifests |

| migration-reviewer | DB migration file add/modify |

| coverage-auditor | any source change (test coverage vs. obligations) |

| architecture-drift-reviewer | code that may diverge from accepted ADRs in .codearbiter/decisions/ |

• Route to dispatching-parallel-agents with that unit list (read-only batch — no collision check).

It dedupes overlapping findings, then funnels through finding-triage (severity + inline

[NEEDS-TRIAGE] on out-of-scope items) → checkpoint-aggregator (single verdict).

• Surface the aggregated verdict: findings by severity, file:line, remediation, and the applicable

control from <project-root>/.codearbiter/security-controls.md for security findings.

• For a PR target, posting the verdict is a separate, confirmed step. Report locally first; post only on explicit instruction, with gh pr review <number> --comment --body-file <file>. A review comment on someone else's PR is outward-facing and effectively public the moment it lands — it notifies subscribers and cannot be un-sent. Never --request-changes or --approve from here: those carry merge authority, and this command produces a finding list, not a maintainer's decision.

Severity

• CRITICAL — exploitable vuln, secret exposure, banned primitive, data-integrity breach.
• HIGH — significant compliance gap or unsafe pattern.
• MEDIUM — standards deviation or coverage gap.
• LOW — informational or style.

Hard gate

Read-only — MUST NOT modify a file, and MUST NOT check out, merge, or otherwise move the repository to the PR's branch: reviewing an inbound PR means reading its DIFF, not adopting its code, and a checkout would run its content through hooks that trust the working tree. BLOCK on any CRITICAL or HIGH finding on your OWN change: it must be resolved before /ca-pr. On an inbound PR there is nothing local to block — the verdict is the deliverable. MUST NOT consume raw reviewer output — only the finding-triage → checkpoint-aggregator

verdict. MUST NOT resolve a [CONFIRM-NN] surfaced during review by guessing.

When NOT to use

• Opening a PR (reviews dispatch automatically) → /ca-pr.
• A periodic full-codebase sweep → /ca-checkpoint.
• A pre-implementation threat model → /ca-threat-model.
• A question about the code → /ca-btw.