Review Elixir/Phoenix Code

Perform an evidence-based, read-only review of changed code. Find and explain issues; do not edit files, create tasks, or fix findings.

Usage

/skill:phx-review
/skill:phx-review test
/skill:phx-review security
/skill:phx-review .claude/plans/auth/plan.md
/skill:phx-review --no-requirements

Treat the text after the skill name as a focus area, issue identifier, or path to a plan/specification.

Iron Laws

1. Review is read-only — inspect and report; never modify the worktree.
2. Scope to changed code — distinguish new defects from pre-existing issues.
3. Every finding needs evidence — cite a path and line, explain impact, and describe the concrete failure mode.
4. Check requirements when available — unmet requirements affect the verdict.
5. Deduplicate and prioritize — one root cause is one finding, with the highest justified severity.
6. Do not require custom agents, hooks, MCP, or unavailable task APIs — use optional runtime capabilities only when present.

Workflow

1. Establish Scope

Determine the merge base or user-specified base, then inspect:

git status --short
git diff --name-only <base>...HEAD
git diff --stat <base>...HEAD
git diff <base>...HEAD -- <changed-files>

Do not assume HEAD~5 is the correct base. Include uncommitted changes when the user asks to review the current worktree. Record the chosen scope in the result.

2. Load Requirements

Unless --no-requirements is set, look for an explicit plan/spec path, current conversation requirements, a branch or commit issue identifier, or the latest relevant plan. Use available integrations or gh issue view when configured; otherwise mark requirements NOT AVAILABLE and continue.

Read references/requirements-detection.md for detection order. Never let a missing Linear, GitHub, hook, or MCP integration block code review.

3. Review by Concern

Select only concerns relevant to the diff:

• Elixir/Phoenix correctness and idioms;
• Ecto queries, changesets, transactions, migrations, and N+1 risks;
• LiveView lifecycle, reconnect, forms, streams, and assigns;
• authentication, authorization, secrets, and input handling;
• Oban idempotency, retries, uniqueness, and transaction boundaries;
• tests, regressions, and verification gaps;
• deployment/runtime configuration when those files changed.

Native Pi subagents may run independent read-only concern tracks in parallel. Use generic subagents with the complete diff scope and return findings to this session; do not depend on separately installed named agents. If subagents are unavailable or unnecessary, run every selected concern sequentially here. A sequential review is fully valid.

4. Verify Findings

For each candidate:

1. Confirm it is in changed code or label it PRE-EXISTING.
2. Trace the actual runtime or data-flow consequence.
3. Check nearby tests and requirements.
4. Remove style-only noise and speculative concerns.
5. Merge duplicates under the clearest root cause.

Run targeted read-only verification when it materially changes confidence. Do not alter files or suppress failures. If a check cannot run, report that clearly.

5. Report a Verdict

Return one verdict:

• PASS
• PASS WITH WARNINGS
• REQUIRES CHANGES
• BLOCKED

List findings in descending severity as BLOCKER, WARNING, or SUGGESTION. Each finding must include path:line, evidence, impact, and the smallest appropriate correction. Add requirements coverage before findings; any UNMET requirement requires REQUIRES CHANGES.

If there are no findings, say so explicitly and list residual risks or checks not run. Stop after presenting the review. Suggest /skill:phx-triage, /skill:phx-plan, or /skill:phx-compound as optional next steps without invoking them automatically.

References

• references/requirements-detection.md — requirements source and coverage rules
• references/agent-spawning.md — Pi concern selection and optional parallelism