diff --git a/.github/workflows/backfill-duplicate-comments.yml b/.github/workflows/backfill-duplicate-comments.yml
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+++ b/.github/workflows/backfill-duplicate-comments.yml
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+name: Backfill Duplicate Comments
+description: Triggers duplicate detection for old issues that don't have duplicate comments
+
+on:
+  workflow_dispatch:
+    inputs:
+      days_back:
+        description: 'How many days back to look for old issues'
+        required: false
+        default: '90'
+        type: string
+      dry_run:
+        description: 'Dry run mode (true to only log what would be done)'
+        required: false
+        default: 'true'
+        type: choice
+        options:
+          - 'true'
+          - 'false'
+
+jobs:
+  backfill-duplicate-comments:
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+    permissions:
+      contents: read
+      issues: read
+      actions: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+      
+      - name: Setup Bun
+        uses: oven-sh/setup-bun@v2
+        with:
+          bun-version: latest
+      
+      - name: Backfill duplicate comments
+        run: bun run scripts/backfill-duplicate-comments.ts
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          DAYS_BACK: ${{ inputs.days_back }}
+          DRY_RUN: ${{ inputs.dry_run }}
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