From d4eaaafb402d208b8c9be4c10043ae0f3a8c5145 Mon Sep 17 00:00:00 2001
From: Dave Cheney <dave@cheney.net>
Date: Tue, 13 Oct 2026 09:40:49 +0900
Subject: [PATCH] ci: reject coding tool attributions in PRs

---
 .github/workflows/commit-check.yml | 34 ++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)
 create mode 100644 .github/workflows/commit-check.yml

diff --git a/.github/workflows/commit-check.yml b/.github/workflows/commit-check.yml
new file mode 100644
index 0000000000..765523d22b
--- /dev/null
+++ b/.github/workflows/commit-check.yml
@@ -0,0 +1,34 @@
+name: Commit check
+
+on:
+  pull_request:
+    types: [opened, edited, synchronize, reopened]
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  no-tool-attribution:
+    # Reject coding tool attributions in commit messages and the PR description.
+    runs-on: ubuntu-slim
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
+      - name: Check commit messages and PR description
+        env:
+          BASE_REF: ${{ github.base_ref }}
+          PR_TITLE: ${{ github.event.pull_request.title }}
+          PR_BODY: ${{ github.event.pull_request.body }}
+        run: |
+          pattern='noreply@anthropic\.com|co-authored-by:.*(claude|copilot|cursor|codex|gemini|aider)|generated (with|by) .*(claude|copilot|cursor|chatgpt|codex|gemini)'
+          {
+            git log --format=%B "origin/$BASE_REF..HEAD"
+            printf '%s\n%s\n' "$PR_TITLE" "$PR_BODY"
+          } > "$RUNNER_TEMP/messages.txt"
+          if grep -inE "$pattern" "$RUNNER_TEMP/messages.txt"; then
+            echo "::error::Remove coding tool attribution from the commit messages and PR description."
+            exit 1
+          fi