merge-winner

name	merge-winner
description	Squash-merge a winning experiment PR and update the baseline. Handles the merge, BASELINE.md update, commit, push, and branch pull. Also handles merge conflicts by sending the PR back for rebase. Use this skill to: merge a winning PR, update baseline, squash merge experiment. Triggers for: "merge winner", "merge this PR", "update baseline after merge", "squash merge".
argument-hint	<pr-number> <problem-dir>
model	claude-sonnet-4-6
effort	high

merge-winner

A PR beat the baseline — merge it and record the new best metrics in BASELINE.md. Comment on the PR saying your are merging it and why if there isn't already a comment.

Arguments

• $0 — The PR number (e.g. 1842)
• $1 — The active problem directory (e.g. target/cfd_tandemfoil)

Note: $ADVISOR_BRANCH is available as an environment variable.

Steps

1. Run the merge preflight. Do not skip this.

The preflight refuses unsafe merges and prints a specific error explaining why: missing terminal results, active hold comments, WIP/draft state, bad labels, or merge conflicts. If it refuses, stop. Do not bypass it with raw gh pr merge; read the error and follow up on the PR.

source "${CLAUDE_PLUGIN_ROOT}/scripts/senpai-gh.sh"
senpai_merge_winner_preflight $0 "$1"

2. Squash-merge the PR:

gh pr merge $0 --squash --repo "$GH_REPO"

If this fails due to merge conflicts, send the PR back for rebase instead:

source "${CLAUDE_PLUGIN_ROOT}/scripts/senpai-gh.sh"
send_pr_back_to_student_with_comment $0 "ADVISOR: Rebasing needed — the advisor branch was updated after merging a previous winner. Please rebase onto $ADVISOR_BRANCH, re-run the experiment to verify the improvement still holds, and resubmit."

Then stop — don't proceed with baseline update.

3. Pull the updated branch:

git checkout "$ADVISOR_BRANCH" && git pull origin "$ADVISOR_BRANCH"

4. Update BASELINE.md by appending the new baseline entry. Read the winning metrics from the PR comments and the W&B run metrics. The entry should include:

## <YYYY-MM-DD HH:MM> — PR #<number>: <title>

- **Surface MAE:** Ux=X.XXXX, Uy=X.XXXX, p=X.XXXX
- **val/loss:** X.XXX
- **W&B run:** <run-id>
- **Reproduce:** `cd "$1" && python train.py <full command>`

5. Commit and push the baseline update:

git add BASELINE.md
git commit -m "Update baseline: <short description> (PR #$0)"
git push origin "$ADVISOR_BRANCH"

After merging

All subsequent PR reviews in this round should compare against the newly updated baseline, not the old one. If you're reviewing multiple winners in a batch, merge them best-first and update the baseline after each one.