pr-drive-to-merge

PR Drive to Merge

Overview

Takes an existing PR/MR and drives it to merge autonomously. Loops through CI/CD monitoring and code review cycles until all requirements are satisfied.

Core principle: Fix only what belongs to the current PR. Ask the user only when a problem is outside the current PR scope and the fix isn't obvious.

Setup

Before starting, detect the PR and platform:

# GitHub — fetch all needed fields in one call
PR_INFO=$(gh pr view --json number,baseRefName,isDraft)
PR_NUMBER=$(echo "$PR_INFO" | jq -r .number)
BASE=$(echo "$PR_INFO" | jq -r .baseRefName)
IS_DRAFT=$(echo "$PR_INFO" | jq -r .isDraft)

# GitLab — detect MR number and base branch
MR_INFO=$(glab mr view --output json)
MR_NUMBER=$(echo "$MR_INFO" | jq .iid)
BASE=$(echo "$MR_INFO" | jq -r .target_branch)
IS_DRAFT=$(echo "$MR_INFO" | jq .draft)

Platform detection: check git remote get-url origin.

• Contains github.com (HTTPS: https://github.com/... or SSH: git@github.com:...) → use gh
• Contains gitlab → use glab

Phase 1: CI/CD Monitoring

digraph cicd {
    rankdir=TB;

    start [label="PR/MR exists", shape=doublecircle];
    fetch_status [label="Fetch current CI/CD status\n+ check if draft", shape=box];
    has_ci [label="CI/CD configured?", shape=diamond];
    ci_state [label="Current state?", shape=diamond];
    wait [label="Poll checks every ~2 min\nuntil complete", shape=box];
    passing [label="All required checks passing?", shape=diamond];
    investigate [label="Investigate failure logs", shape=box];
    our_fault [label="Caused by current changes?", shape=diamond];
    fix [label="Fix → invoke prepare-for-pr\n→ push", shape=box];
    ask [label="Ask user", shape=box];
    undraft [label="Undraft PR/MR\nif still draft", shape=box];
    review [label="Proceed to Code Review", shape=box];

    start -> fetch_status;
    fetch_status -> has_ci;
    has_ci -> ci_state [label="yes"];
    has_ci -> undraft [label="no CI"];
    ci_state -> wait [label="pending/running"];
    ci_state -> passing [label="complete"];
    wait -> passing;
    passing -> undraft [label="yes"];
    passing -> investigate [label="no"];
    investigate -> our_fault;
    our_fault -> fix [label="yes"];
    our_fault -> ask [label="no — pause\nuntil user decides"];
    ask -> fetch_status [label="user decides"];
    fix -> wait;
    undraft -> review;
}

Invoking prepare-for-pr for fixes: invoke it as a sub-skill. It runs its own quality loop, commits fixes, and exits when clean. If it pauses for user input, this skill also pauses. After it exits, push: git push.

Phase 2: Code Review Cycle

digraph review {
    rankdir=TB;

    start [label="CI/CD passing", shape=doublecircle];
    read_all [label="Read ALL comments\n(reviews + inline review comments)", shape=box];
    any_comments [label="Any unaddressed\ncomments?", shape=diamond];
    categorize [label="Categorize + show table\n(BLOCKING/IMPORTANT/OPTIONAL\n/INVALID/OUT OF SCOPE)", shape=box];
    oos_present [label="OUT OF SCOPE\ncomments?", shape=diamond];
    ask_oos [label="Ask user for each OUT OF SCOPE\ncomment. Pause until resolved.", shape=box];
    respond_optional [label="Respond to OPTIONAL and\nnon-praise INVALID immediately", shape=box];
    any_fix [label="Any BLOCKING or\nIMPORTANT comments?", shape=diamond];
    push [label="Fix → prepare-for-pr → push", shape=box];
    respond_fixed [label="Respond to BLOCKING/IMPORTANT\nwith commit hash", shape=box];
    resolve [label="Resolve all threads", shape=box];
    fixes_made [label="Push was made\n(BLOCKING/IMPORTANT fixed)?", shape=diamond];
    rereview [label="Request re-review from reviewers\nwhose comments led to changes", shape=box];
    wait [label="Wait for re-review\n(poll every ~5 min)", shape=box];
    stale_check [label="No activity for\n>4 hours?", shape=diamond];
    notify_stale [label="Notify user, ask\nhow to proceed. Pause.", shape=box];
    new_comments [label="New unaddressed\ncomments?", shape=diamond];
    confirm_merge [label="Verify merge requirements checklist.\nIf all met, ask user:\n'Ready to merge — should I go ahead?'", shape=box];
    done [label="MERGE", shape=doublecircle];

    start -> read_all;
    read_all -> any_comments;
    any_comments -> categorize [label="yes"];
    any_comments -> confirm_merge [label="no"];
    categorize -> oos_present;
    oos_present -> ask_oos [label="yes"];
    oos_present -> respond_optional [label="no"];
    ask_oos -> respond_optional [label="user decided"];
    respond_optional -> any_fix;
    any_fix -> push [label="yes"];
    any_fix -> resolve [label="no"];
    push -> respond_fixed;
    respond_fixed -> resolve;
    resolve -> fixes_made;
    fixes_made -> rereview [label="yes — push\nwas made"];
    fixes_made -> confirm_merge [label="no — only optional/\ninvalid addressed"];
    rereview -> wait;
    wait -> stale_check;
    stale_check -> notify_stale [label="yes"];
    notify_stale -> wait [label="user responds"];
    stale_check -> new_comments [label="no"];
    new_comments -> read_all [label="yes — repeat"];
    new_comments -> confirm_merge [label="no"];
    confirm_merge -> done [label="user confirms"];
}

Reading comments: gh pr view <N> --comments does not return inline review comments. Fetch them separately:

# GitHub — inline review comments
gh api repos/{owner}/{repo}/pulls/{number}/comments

# GitLab — all discussions (includes inline)
glab api /projects/:fullpath/merge_requests/:iid/discussions

Handling Unclear Feedback

Ask for clarification on ALL unclear items at once — not one at a time. Example:

Reviewer: "Fix 1-6"
You understand 1,2,3,6. Unclear on 4,5.

Wrong: Implement 1,2,3,6 now, ask about 4,5 later
Right: "I understand items 1,2,3,6. Need clarification on 4 and 5 before proceeding."

Verifying Suggestions and Pushing Back

Before implementing any BLOCKING or IMPORTANT suggestion, verify it first:

1. Check: Technically correct for THIS codebase?
2. Check: Would it break existing functionality?
3. Check: Is there a reason the current code is written this way?
4. Check: Works on all platforms/versions targeted by this PR?
5. Check: Does the reviewer have full context?

If any check fails — push back:

• Use technical reasoning, not defensiveness
• Ask specific questions; reference working tests or existing code as evidence
• Involve the user if the disagreement is architectural
• State it factually in the response thread — no apology, no over-explaining

If you can't easily verify: say so — "I can't verify this without [X]. Should I [investigate/ask/proceed]?"

If it conflicts with prior decisions for this PR: discuss with user first.

YAGNI check — if a reviewer suggests "implementing it properly" or adding infrastructure: search codebase for actual usage. If unused: push back. If used: implement properly.

Comment Categories

Assign ONE category per comment. Show full table before acting. Proceed without waiting for approval except for OUT OF SCOPE.

Category	When to use	Action
BLOCKING	Security issues, critical bugs, compliance violations	Verify → Fix → respond → Resolve
IMPORTANT	Bugs, missing error handling, missing tests	Verify → Fix → respond → Resolve
OPTIONAL	Style, naming preference, refactoring suggestion, nitpick	Respond acknowledging → Resolve without fixing
INVALID	Already fixed, no longer applies	Respond acknowledging → Resolve
INVALID (praise)	Compliments, thanks	Resolve without responding
OUT OF SCOPE	Requires changes outside this PR	Ask user before acting

Show table format:

## PR Review Comments

| # | Author | Location | Summary | Category | Action |
|---|--------|----------|---------|----------|--------|
| 1 | @dev | auth.ts:23 | Password in plaintext | BLOCKING | Will fix |
| 2 | @dev | auth.ts:12 | Rename doAuth | OPTIONAL | Will acknowledge |
| 3 | @qa | auth.ts:45 | Missing error handling | IMPORTANT | Will fix |
| 4 | @dev | auth.ts:67 | Nice work! | INVALID (praise) | Will resolve |
| 5 | @dev | utils.ts:10 | Whole file needs refactor | OUT OF SCOPE | Need your input |

Proceeding with BLOCKING + IMPORTANT fixes. Waiting on your input for OUT OF SCOPE (#5).

Responding to Comments

Reply in the comment thread when possible. For fixed comments: respond after pushing, referencing the commit hash. For all others: respond immediately.

# GitHub — reply to an inline review comment (omit pull number — it's not part of this endpoint)
gh api repos/{owner}/{repo}/pulls/comments/{comment_id}/replies \
  --method POST -f body="Your reply here"

# GitHub — reply to a review summary or top-level PR comment (not an inline thread)
gh pr comment $PR_NUMBER --body "Your reply here"

No performative agreement. Never write "You're absolutely right!", "Great point!", "Excellent feedback!", or thank the reviewer. Actions speak — just fix it and show what changed.

Category	Response template
BLOCKING/IMPORTANT (fixed)	Fixed in [commit hash]. [What changed and why.]
BLOCKING/IMPORTANT (pushed back, then verified correct)	Checked [X] — confirmed it does [Y]. Fixed in [commit hash].
BLOCKING/IMPORTANT (pushing back)	[Technical reasoning]. [Evidence from codebase.] Leaving as-is.
OPTIONAL	Not addressing in this PR to keep it focused on [goal]. (If genuinely useful: "Logged as [issue link] for follow-up.")
INVALID (outdated)	This was addressed in [commit]. [File/code] now [does X].
INVALID (praise)	(no response needed — just resolve)
OUT OF SCOPE	Per user's instruction

Resolving Threads

After responding, resolve threads where the issue is closed. Do NOT resolve if discussion is ongoing or awaiting reviewer confirmation.

# GitHub — resolve review thread via GraphQL
# 1. Get thread node IDs:
gh api graphql -f query='
  query($owner:String!,$repo:String!,$number:Int!) {
    repository(owner:$owner,name:$repo) {
      pullRequest(number:$number) {
        reviewThreads(first:100) { nodes { id isResolved } }
      }
    }
  }
' -f owner=OWNER -f repo=REPO -F number=N

# 2. Resolve a thread:
gh api graphql -f query='
  mutation($id:ID!) { resolveReviewThread(input:{threadId:$id}) { thread { isResolved } } }
' -f id=THREAD_NODE_ID

# GitLab — resolve a discussion:
glab api /projects/:fullpath/merge_requests/:iid/discussions/:discussion_id \
  --method PUT -f resolved=true

Re-Review

Request re-review only from reviewers whose BLOCKING or IMPORTANT comments led to actual changes. Do not re-request from reviewers who only left OPTIONAL or INVALID comments.

# GitHub — re-request review (use API, not --add-reviewer which only adds new reviewers)
REPO=$(gh repo view --json nameWithOwner -q .nameWithOwner)
gh api --method POST /repos/$REPO/pulls/$PR_NUMBER/requested_reviewers \
  -f "reviewers[]=username1" -f "reviewers[]=username2"

# GitLab — re-request review via API (glab mr update has no --reviewer flag)
PROJECT_ID=$(glab repo view --output json | jq -r '.id')
# Build reviewer_ids[] args for each username
REVIEWER_ARGS=()
for username in username1 username2; do
  id=$(glab api "/users?username=${username}" --jq '.[0].id')
  REVIEWER_ARGS+=(-f "reviewer_ids[]=${id}")
done
glab api /projects/$PROJECT_ID/merge_requests/$MR_NUMBER --method PUT "${REVIEWER_ARGS[@]}"

Merge Requirements Checklist

Before merging, verify all of:

• All required CI/CD checks pass
• Required approvals received
• No unresolved blocking threads
• Branch up to date with base branch

When all boxes are checked, stop and ask the user for confirmation:

All merge requirements are met — CI passing, approvals received, all threads resolved, branch up to date. Should I go ahead and merge?

Only merge after explicit confirmation. Exception: if the user already pre-approved the merge earlier in the conversation (e.g. "merge it when it's ready"), proceed without asking again.

Branch behind base — check after every push and before merging. If behind:

# GitHub
gh pr update-branch <PR_NUMBER>
# or: git fetch origin $BASE && git rebase origin/$BASE
# If rebase produces conflicts:
#   resolve manually → git add <resolved files> → git rebase --continue
#   if conflicts touch files outside this PR scope → ask user before proceeding
git push --force-with-lease

# GitLab
glab mr rebase <MR_NUMBER>
# If conflict: resolve manually, then git push --force-with-lease

Tools Priority

Prefer CLI → REST API → MCP in that order. Platform detection is covered in Setup.