PR Review Panel

Two independent reviewers, different models, no shared context. Their outputs are saved, consolidated, shown to the operator, and only then posted.

The panel exists to disagree with itself. Two models that saw the same summary produce the same blind spots, so each reviewer reads the diff itself and neither sees the other's output until consolidation.

Non-negotiable: nothing reaches GitHub without operator approval

Never post, comment on, approve, or request changes on a PR until the operator has read the consolidated review and said to post it. Show them the full text, in the conversation, and wait.

This is a hard gate, not a nicety: a review posted under the operator's account is them speaking to a colleague. Two models agreeing is not evidence — they can be confidently wrong together, and a wrong "request changes" costs someone real time.

If the operator is unavailable, save the consolidation and stop.

1. Gather the PR once

gh pr view <PR> --json number,title,body,headRefName,baseRefName,additions,deletions
gh pr diff <PR> > <scratch>/pr-<PR>.diff
gh pr view <PR> --comments
gh issue view <linked-issue>            # scope often lives here, and moves

Scratch dir: use the session scratchpad if one exists, else /tmp/pr-review-<PR>/. Never write review artefacts into the repo — they are not repo content.

Read the linked issue and its comments, in date order. Scope gets revised in comments without the body being updated; a reviewer working from a stale body reports the wrong things.

2. Run both reviewers in parallel

Both get: the diff path, the PR body, the issue and its comments, and the repo path. Neither gets the other's output.

Reviewer A — Fable subagent. Spawn via the Agent tool with model: "fable".

Reviewer B — codex gpt-5.6-sol at xhigh.

codex exec -m gpt-5.6-sol -c model_reasoning_effort=xhigh "<prompt>" > <scratch>/review-codex.md 2>&1

Run it backgrounded — xhigh is slow.

Give both the same brief:

• Judge correctness first: does it do what the ticket asks, and does it break anything else?
• Trace surrounding code, not just changed lines. A diff that reads fine can still be wrong in context.
• Check the tests actually pin the behaviour — would they fail if the fix were reverted? A test that passes either way is a finding.
• Flag anything security-, data-integrity-, or migration-shaped explicitly.
• Cite file:line for every finding. A finding without a location is not actionable.
• Rank by severity: blocking / high / medium / low.
• Say plainly when something looks right. A review that only lists problems is not a review.
• Do not restate the diff back.

Save each raw verdict: <scratch>/review-fable.md, <scratch>/review-codex.md. Keep them — the operator may want to see who said what.

3. Consolidate

Merge into one review. This is judgement work, not concatenation:

• Both flagged it → lead with it, note the agreement.
• One flagged it → keep it if the code supports it. Check the claim against the file yourself before promoting it.
• They disagree → say so explicitly and give your own read, with the evidence. Do not average two positions into mush.
• Either is wrong → drop it and say you dropped it. Passing on a bogus finding wastes the author's time and costs you credibility on the real ones.

Deduplicate hard: the same defect described twice is one finding.

Output: a short summary line, findings by severity with file:line, what looks good, and a recommendation — approve / comment / request changes.

4. Operator gate

Show the operator the consolidated text and the recommendation. Say which findings each reviewer contributed, and name anything you dropped and why.

Then stop and wait.

5. Post, once told to

gh pr review <PR> --comment --body-file <scratch>/review-final.md
# or --request-changes / --approve, per the operator's instruction

Use the verdict the operator chose, not the one you recommended. Report the URL.

Rules

• Never post before the gate, even when both reviewers agree and the finding looks obvious.
• Never file follow-on issues from a review. Findings go in the review; the author decides what becomes a ticket.
• Never edit the PR, its branch, or its description as part of reviewing it.
• If a reviewer fails or returns nothing, say so — do not silently ship a one-model review as a panel.