diff --git a/.github/workflows/internal-ci-trigger.yml b/.github/workflows/internal-ci-trigger.yml
new file mode 100644
index 000000000..9225a1a80
--- /dev/null
+++ b/.github/workflows/internal-ci-trigger.yml
@@ -0,0 +1,281 @@
+# MVP: Trigger internal ADO pipeline from GitHub PR comments.
+# Production version will add: private repo ref push, CredScan redaction,
+# and fork PR support.
+name: Internal CI Trigger
+run-name: "Internal CI for PR #${{ github.event.issue.number }}"
+
+on:
+  issue_comment:
+    types: [created]
+
+jobs:
+  trigger-internal-ci:
+    # Only run on PR comments (not issue comments) that are /test commands.
+    if: >-
+      github.event.issue.pull_request
+      && (
+        github.event.comment.body == '/test'
+        || startsWith(github.event.comment.body, '/test ')
+      )
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      issues: write
+      pull-requests: read
+      statuses: write
+    steps:
+      - name: Validate test command
+        env:
+          COMMENT_BODY: ${{ github.event.comment.body }}
+        run: |
+          if [[ ! "$COMMENT_BODY" =~ ^/test([[:space:]]+force)?[[:space:]]*$ ]]; then
+            echo "::error::Unsupported internal CI command. Use /test or /test force."
+            exit 1
+          fi
+
+      - name: Check authorization
+        id: auth
+        env:
+          GH_TOKEN: ${{ github.token }}
+          MICROSOFT_GITHUB_ORG: microsoft
+          MS_ORG_READ_TOKEN: ${{ secrets.MS_ORG_READ_TOKEN }}
+        run: |
+          COMMENTER="${{ github.event.comment.user.login }}"
+
+          # Check if the commenter has write access to the repo
+          PERMISSION=$(gh api "repos/${{ github.repository }}/collaborators/${COMMENTER}/permission" \
+            --jq '.permission')
+
+          if [[ "$PERMISSION" != "admin" && "$PERMISSION" != "write" ]]; then
+            echo "::error::User ${COMMENTER} does not have write access (permission: ${PERMISSION})"
+            exit 1
+          fi
+
+          if [[ -z "${MS_ORG_READ_TOKEN:-}" ]]; then
+            echo "::error::MS_ORG_READ_TOKEN secret is required to verify Microsoft org membership"
+            exit 1
+          fi
+
+          if ! GH_TOKEN="$MS_ORG_READ_TOKEN" gh api "orgs/${MICROSOFT_GITHUB_ORG}/members/${COMMENTER}" --silent; then
+            echo "::error::User ${COMMENTER} is not a member of ${MICROSOFT_GITHUB_ORG}, or membership could not be verified"
+            exit 1
+          fi
+
+          echo "authorized=true" >> "$GITHUB_OUTPUT"
+          echo "User ${COMMENTER} authorized (permission: ${PERMISSION}, org: ${MICROSOFT_GITHUB_ORG})"
+
+      - name: React to comment
+        continue-on-error: true
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          gh api "repos/${{ github.repository }}/issues/comments/${{ github.event.comment.id }}/reactions" \
+            -f content='eyes' --silent
+
+      - name: Get PR details and pinned SHA
+        id: pr
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          PR_NUMBER="${{ github.event.issue.number }}"
+
+          PR_DATA=$(gh api "repos/${{ github.repository }}/pulls/${PR_NUMBER}" \
+            --jq '{sha: .head.sha, branch: .head.ref, head_repo: .head.repo.full_name, base_repo: .base.repo.full_name}')
+
+          COMMIT_SHA=$(echo "$PR_DATA" | jq -r '.sha')
+          SOURCE_BRANCH=$(echo "$PR_DATA" | jq -r '.branch')
+          HEAD_REPO=$(echo "$PR_DATA" | jq -r '.head_repo')
+          BASE_REPO=$(echo "$PR_DATA" | jq -r '.base_repo')
+
+          # MVP: reject fork PRs — they require additional handling
+          if [[ "$HEAD_REPO" != "$BASE_REPO" ]]; then
+            echo "::error::Fork PRs are not supported yet (head: ${HEAD_REPO}, base: ${BASE_REPO})"
+            exit 1
+          fi
+
+          echo "commit_sha=${COMMIT_SHA}" >> "$GITHUB_OUTPUT"
+          echo "source_branch=${SOURCE_BRANCH}" >> "$GITHUB_OUTPUT"
+          echo "pr_number=${PR_NUMBER}" >> "$GITHUB_OUTPUT"
+
+          echo "PR #${PR_NUMBER} at SHA ${COMMIT_SHA} (branch: ${SOURCE_BRANCH})"
+
+      - name: Path filter — skip if only irrelevant files changed
+        id: pathfilter
+        env:
+          GH_TOKEN: ${{ github.token }}
+          COMMENT_BODY: ${{ github.event.comment.body }}
+        run: |
+          PR_NUMBER="${{ steps.pr.outputs.pr_number }}"
+
+          # Allow override: `/test force` bypasses the path filter
+          if echo "$COMMENT_BODY" | grep -qiE '^/test[[:space:]]+force\b'; then
+            echo "Path filter bypassed via '/test force'"
+            echo "skip=false" >> "$GITHUB_OUTPUT"
+            exit 0
+          fi
+
+          # Files matching any of these patterns are considered irrelevant to internal CI.
+          # If the PR touches *only* these, we skip the expensive run.
+          IGNORE_PATTERNS=(
+            '*.md'
+            '**/*.md'
+            'LICENSE'
+            'NOTICE'
+            'CODEOWNERS'
+            'MAINTAINERS.md'
+            '.gitignore'
+            '.gitattributes'
+            'docs/**'
+            '.github/**'
+            'rfcs/**'
+            'licenses/**'
+          )
+
+          # Get list of changed files (paginated, up to 3000)
+          mapfile -t FILES < <(gh api --paginate \
+            "repos/${{ github.repository }}/pulls/${PR_NUMBER}/files" \
+            --jq '.[].filename')
+
+          if [[ ${#FILES[@]} -eq 0 ]]; then
+            echo "::warning::No files reported changed; running CI anyway"
+            echo "skip=false" >> "$GITHUB_OUTPUT"
+            exit 0
+          fi
+
+          echo "Changed files (${#FILES[@]}):"
+          printf '  %s\n' "${FILES[@]}"
+
+          shopt -s globstar extglob nullglob
+          RELEVANT=0
+          for f in "${FILES[@]}"; do
+            matched=0
+            for pat in "${IGNORE_PATTERNS[@]}"; do
+              # shellcheck disable=SC2053
+              if [[ "$f" == $pat ]]; then
+                matched=1
+                break
+              fi
+            done
+            if [[ $matched -eq 0 ]]; then
+              echo "Relevant file: $f"
+              RELEVANT=1
+              break
+            fi
+          done
+
+          if [[ $RELEVANT -eq 0 ]]; then
+            echo "All changed files match ignore patterns — skipping internal CI"
+            echo "skip=true" >> "$GITHUB_OUTPUT"
+
+            gh api "repos/${{ github.repository }}/issues/${PR_NUMBER}/comments" \
+              -f body="⏭️ Internal CI skipped: PR only touches docs/CI/license files. Use \`/test force\` to override." \
+              --silent
+          else
+            echo "skip=false" >> "$GITHUB_OUTPUT"
+          fi
+
+      - name: Set pending commit status
+        if: steps.pathfilter.outputs.skip != 'true'
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          gh api "repos/${{ github.repository }}/statuses/${{ steps.pr.outputs.commit_sha }}" \
+            -f state='pending' \
+            -f description='Internal CI triggered, waiting for results...' \
+            -f context='ms-internal-ci/oss-jstests' \
+            --silent
+
+      - name: POST webhook to ADO
+        if: steps.pathfilter.outputs.skip != 'true'
+        env:
+          MS_WEBHOOK_SECRET: ${{ secrets.MS_WEBHOOK_SECRET }}
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          PR_NUMBER="${{ steps.pr.outputs.pr_number }}"
+          COMMIT_SHA="${{ steps.pr.outputs.commit_sha }}"
+          SOURCE_BRANCH="${{ steps.pr.outputs.source_branch }}"
+
+          if [[ -z "${MS_WEBHOOK_SECRET:-}" ]]; then
+            echo "::error::MS_WEBHOOK_SECRET secret is required to trigger ADO"
+            exit 1
+          fi
+
+          # Build a comment-shaped payload so each /test comment is a distinct
+          # webhook event while still carrying the pinned PR SHA for ADO.
+          PAYLOAD=$(jq -n \
+            --arg action "created" \
+            --arg pr_number "$PR_NUMBER" \
+            --arg sha "$COMMIT_SHA" \
+            --arg branch "$SOURCE_BRANCH" \
+            --arg repo "${{ github.repository }}" \
+            --arg triggerer "${{ github.event.comment.user.login }}" \
+            --arg comment_id "${{ github.event.comment.id }}" \
+            --arg comment_url "${{ github.event.comment.html_url }}" \
+            --arg comment_created_at "${{ github.event.comment.created_at }}" \
+            '{
+              action: $action,
+              number: ($pr_number | tonumber),
+              triggerer: $triggerer,
+              comment: {
+                id: ($comment_id | tonumber),
+                html_url: $comment_url,
+                created_at: $comment_created_at,
+                user: {
+                  login: $triggerer
+                }
+              },
+              issue: {
+                number: ($pr_number | tonumber),
+                pull_request: {
+                  url: "https://api.github.com/repos/\($repo)/pulls/\($pr_number)"
+                }
+              },
+              repository: {
+                full_name: $repo
+              },
+              pull_request: {
+                html_url: "https://github.com/\($repo)/pull/\($pr_number)",
+                head: {
+                  sha: $sha,
+                  ref: $branch,
+                  repo: {
+                    full_name: $repo
+                  }
+                },
+                base: {
+                  ref: "main"
+                },
+                user: {
+                  login: $triggerer
+                }
+              }
+            }')
+
+          # Compute the raw HMAC-SHA1 hex signature expected by the ADO
+          # documentdb-oss-external-ci-webhook service connection. Unsigned
+          # and bad-signature requests must fail before queuing ADO pipeline 56298.
+          SIGNATURE=$(echo -n "$PAYLOAD" | openssl dgst -sha1 -hmac "$MS_WEBHOOK_SECRET" -binary | xxd -p -c 256)
+
+          # POST to ADO incoming webhook endpoint
+          HTTP_STATUS=$(curl -sS -o /dev/null -w "%{http_code}" \
+            -X POST \
+            -H "Content-Type: application/json" \
+            -H "X-GitHub-ADO-Signature: $SIGNATURE" \
+            -d "$PAYLOAD" \
+            "https://dev.azure.com/msdata/_apis/public/distributedtask/webhooks/documentdb-oss-external-ci-webhook?api-version=6.0-preview")
+
+          echo "ADO webhook response: HTTP ${HTTP_STATUS}"
+
+          if [[ "$HTTP_STATUS" -lt 200 || "$HTTP_STATUS" -ge 300 ]]; then
+            echo "::error::ADO webhook POST failed with HTTP ${HTTP_STATUS}"
+
+            # Set error status so the PR doesn't stay pending forever
+            gh api "repos/${{ github.repository }}/statuses/${COMMIT_SHA}" \
+              -f state='error' \
+              -f description='Failed to trigger internal CI pipeline' \
+              -f context='ms-internal-ci/oss-jstests' \
+              --silent
+            exit 1
+          fi
+
+          echo "Webhook triggered successfully"