git rev-parse --abbrev-ref HEAD # save original branch
git stash push -m "Stashing before checks setup"
git checkout -b add-checks

gh pr list --state merged --limit 30 --json number,title
# For 3-5 recent PRs with review comments:
gh api repos/{owner}/{repo}/pulls/{number}/comments --jq '.[] | {body: .body, path: .path}'

---
name: Human-Readable Check Name
description: One-sentence description.
---

# Check Name

## Context

WHY this check exists. Reference specific project patterns, configs, or review comments you found.

## What to Check

### 1. Category

Concrete instructions with specific file paths/patterns and GOOD/BAD code examples from this codebase.

### 2. Category

...

## Key Files

List the files most relevant to this check.

## Exclusions

Cases where this check does NOT apply.

## Checks

Before opening a pull request, run all checks in `.checks/` against your current diff and fix any failures before requesting review.

name: AI Checks

on:
  pull_request:
    types: [opened, synchronize, reopened]

concurrency:
  group: ai-checks-${{ github.event.pull_request.number }}
  cancel-in-progress: true

jobs:
  checks:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: write
      checks: write
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - uses: actions/cache@v4
        with:
          path: ~/.npm
          key: claude-code-${{ runner.os }}

      - name: Install agent CLI
        run: npm install -g @anthropic-ai/claude-code

      - name: Get PR diff
        run: |
          gh pr diff ${{ github.event.pull_request.number }} > /tmp/pr.diff
          head -c 100000 /tmp/pr.diff > /tmp/pr-truncated.diff
        env:
          GH_TOKEN: ${{ github.token }}

      - name: Run all checks
        env:
          ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
          GH_TOKEN: ${{ github.token }}
        run: |
          REPORT_FILE=$(mktemp)
          echo "## AI Check Results" >> "$REPORT_FILE"
          echo "" >> "$REPORT_FILE"
          echo "| Check | Result |" >> "$REPORT_FILE"
          echo "|---|---|" >> "$REPORT_FILE"

          for check_file in .checks/*.md; do
            [ -f "$check_file" ] || continue
            name=$(basename "$check_file" .md)

            # Create check run in progress
            CHECK_RUN_ID=$(gh api repos/${{ github.repository }}/check-runs \
              -f name="check/$name" \
              -f head_sha=${{ github.event.pull_request.head.sha }} \
              -f status=in_progress \
              --jq '.id')

            # Run agent with the check prompt and PR diff
            OUTPUT=$(claude -p "$(cat <<PROMPT
          You are running a quality check on a pull request.

          ## Check
          $(cat "$check_file")

          ## PR Diff
          $(cat /tmp/pr-truncated.diff)

          ## Instructions
          Evaluate the changed files against this check.
          Only review changed lines. Do not flag pre-existing issues in unchanged code.
          Output valid JSON: {"verdict":"PASS" or "FAIL","reason":"...","suggestions":[{"file":"...","line":0,"fix":"..."}]}
          PROMPT
            )" --output-format json 2>&1) || true

            # Parse verdict — claude --output-format json wraps the response in an envelope
            # with the actual content in .result as a string (possibly markdown-fenced)
            INNER=$(echo "$OUTPUT" | jq -r '.result // empty' 2>/dev/null | sed 's/^```json//;s/^```//;s/```$//' | jq -r '.' 2>/dev/null || echo "$OUTPUT")
            VERDICT=$(echo "$INNER" | jq -r '.verdict // "ERROR"' 2>/dev/null || echo "ERROR")
            REASON=$(echo "$INNER" | jq -r '.reason // "No reason given"' 2>/dev/null || echo "Parse failure")

            # Extract suggestions for detail text
            SUGGESTIONS=$(echo "$INNER" | jq -r '.suggestions // [] | .[] | "- **\(.file):\(.line)** — \(.fix)"' 2>/dev/null || echo "")

            # Build detail markdown
            DETAIL="## $name\n\n**Verdict:** $VERDICT\n\n### Reason\n\n$REASON"
            if [ -n "$SUGGESTIONS" ]; then
              DETAIL="$DETAIL\n\n### Suggestions\n\n$SUGGESTIONS"
            fi

            # Complete the check run
            CONCLUSION=$([ "$VERDICT" = "PASS" ] && echo "success" || echo "failure")
            gh api repos/${{ github.repository }}/check-runs/$CHECK_RUN_ID \
              -X PATCH \
              -f status=completed \
              -f conclusion="$CONCLUSION" \
              -f "output[title]=$(echo "$REASON" | head -c 140)" \
              -f "output[summary]=$REASON" \
              -f "output[text]=$(printf "$DETAIL")" > /dev/null

            # Append to report
            ICON=$([ "$VERDICT" = "PASS" ] && echo "✅" || echo "❌")
            echo "| $ICON $name | $REASON |" >> "$REPORT_FILE"

            # Save full output for debugging
            echo "$OUTPUT" > "/tmp/check-$name.json"
          done

          # Post single consolidated comment
          gh pr comment ${{ github.event.pull_request.number }} --body "$(cat "$REPORT_FILE")"

      - name: Upload check outputs
        if: always()
        uses: actions/upload-artifact@v4
        with:
          name: check-results
          path: /tmp/check-*.json
          retention-days: 7

git add .checks/
git add .github/workflows/checks.yml 2>/dev/null # if CI was set up
git add CLAUDE.md AGENTS.md COPILOT.md 2>/dev/null # whichever was modified
git commit -m "Add checks for automated PR review

Checks:
- [list each check name]"
git push origin HEAD
gh pr create --title "Add checks for automated PR review" --body "Adds AI-powered code review checks that run on every PR.

## Checks added

[list each check with one-line description]

## How it works

Each check is a markdown file in \`.checks/\`. They run as full agents on every PR — reading files, running commands, and providing suggested fixes when they find issues."

git checkout <original-branch>
git stash pop