diff --git a/.github/workflows/build_x86_64_mlu.yaml b/.github/workflows/build_x86_64_mlu.yaml
index 065ee453..8ef4841b 100644
--- a/.github/workflows/build_x86_64_mlu.yaml
+++ b/.github/workflows/build_x86_64_mlu.yaml
@@ -18,8 +18,6 @@ on:
     branches: [main]
     types: [opened, synchronize, reopened]
     paths-ignore:
-      - '.github/**'
-      - 'cibuild/**'
       - 'cmake/**'
       - 'docs/**'
       - 'third_party/**'
@@ -27,7 +25,16 @@ on:
       - '*.md'
       - '*.txt'
       - '*.yml'
-
+  pull_request_review:
+    types: [submitted]
+    paths-ignore:
+      - 'cmake/**'
+      - 'docs/**'
+      - 'third_party/**'
+      - 'tools/**'
+      - '*.md'
+      - '*.txt'
+      - '*.yml'
 env:
   JOBNAME: xllm-x86_64-mlu-cibuild-${{ github.run_id }}
 
@@ -36,8 +43,128 @@ concurrency:
   cancel-in-progress: ${{ startsWith(github.ref, 'refs/pull/') }}
 
 jobs:
+  # need to review code first when sensitive files are modified.
+  check-sensitive-step-1:
+    runs-on: [self-hosted]
+    outputs:
+      should_check: ${{ steps.decide.outputs.should_check }}
+      approved: ${{ steps.decide.outputs.approved }}
+    steps:
+      - name: Decide whether to check sensitive file
+        id: decide
+        run: |
+          event="${{ github.event_name }}"
+          if [[ "$event" == "workflow_dispatch" || "$event" == "push" ]]; then
+            echo "ignore workflow_dispatch and push events in check-sensitive-step-1."
+            echo "should_check=false" >> $GITHUB_OUTPUT
+            echo "approved=false" >> $GITHUB_OUTPUT
+          elif [[ "$event" == "pull_request" ]]; then
+            echo "should_check=true" >> $GITHUB_OUTPUT
+            echo "approved=false" >> $GITHUB_OUTPUT
+          elif [[ "$event" == "pull_request_review" ]]; then
+            if [[ "${{ github.event.review.state }}" == "approved" ]]; then
+              echo "should_check=false" >> $GITHUB_OUTPUT
+              echo "approved=true" >> $GITHUB_OUTPUT
+            else
+              echo "should_check=false" >> $GITHUB_OUTPUT
+              echo "approved=false" >> $GITHUB_OUTPUT
+            fi
+          else
+            echo "should_check=false" >> $GITHUB_OUTPUT
+            echo "approved=false" >> $GITHUB_OUTPUT
+          fi
+
+  check-sensitive-step-2:
+    needs: check-sensitive-step-1
+    #if: >
+    #  needs.check-sensitive-step-1.outputs.should_check == 'true' &&
+    #  (github.event_name == 'pull_request' || github.event_name == 'pull_request_review')
+    if: >
+      needs.check-sensitive-step-1.outputs.should_check == 'true' && github.event_name == 'pull_request'
+    runs-on: [self-hosted]
+    outputs:
+      do_build: ${{ steps.check.outputs.do_build }}
+    steps:
+      - name: Checkout Code
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0  # Ensure we can compare commits
+
+      - name: Install jq
+        run: yum install -y jq
+
+      - name: Check if sensitive files were changed
+        id: check_sensitive
+        run: |
+          sensitive_files=(
+            ".github/**.yaml"
+            "cibuild/**.sh"
+            "setup.py"
+          )
+          changed_files=$(git diff --name-only ${{ github.event.pull_request.base.sha }} ${{ github.sha }})
+          requires_approval="false"
+          while IFS= read -r changed_file; do
+            [[ -z "$changed_file" ]] && continue
+            for pattern in "${sensitive_files[@]}"; do
+              if [[ "$changed_file" == $pattern ]]; then
+                requires_approval="true"
+                break 2
+              fi
+          done
+          done < <(git diff --name-only "${{ github.event.pull_request.base.sha }}" "${{ github.sha }}")
+
+          echo "requires_approval=$requires_approval" >> $GITHUB_OUTPUT
+
+      - name: Check PR approvals
+        id: check_approved
+        if: ${{ github.event_name == 'pull_request' && steps.check_sensitive.outputs.requires_approval == 'true' }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          pr_number=${{ github.event.pull_request.number }}
+          response=$(curl -s -H "Authorization: Bearer $GITHUB_TOKEN" \
+            -H "Accept: application/vnd.github.v3+json" \
+            "https://api.github.com/repos/${{ github.repository }}/pulls/$pr_number/reviews")
+
+          if echo "$response" | jq -e '.[] | select(.state == "APPROVED")' > /dev/null; then
+            echo "approved=true" >> $GITHUB_OUTPUT
+          else
+            echo "approved=false" >> $GITHUB_OUTPUT
+          fi
+
+      - name: Final check
+        id: check
+        run: |
+          if [ "${{ steps.check_sensitive.outputs.requires_approval }}" != "true" ]; then
+            echo "do_build=true" >> $GITHUB_OUTPUT
+          elif [ "${{ steps.check_approved.outputs.approved }}" == "true" ]; then
+            echo "do_build=true" >> $GITHUB_OUTPUT
+          else
+            echo "do_build=false" >> $GITHUB_OUTPUT
+          fi
+
+  check-sensitive-step-3:
+    needs: check-sensitive-step-1
+    if: >
+      github.event_name == 'pull_request_review'
+    runs-on: [self-hosted]
+    outputs:
+      do_build: ${{ steps.check.outputs.do_build }}
+    steps:
+      - name: Checkout status
+        id: check
+        run:
+          if [ "${{ needs.check-sensitive-step-1.outputs.approved }}" == "true" ]; then
+            echo "do_build=true" >> $GITHUB_OUTPUT
+          else
+            echo "do_build=false" >> $GITHUB_OUTPUT
+          fi
+
   build:
-    if: ${{ github.event_name == 'workflow_dispatch' || github.event_name == 'push' || github.event_name == 'pull_request' }}
+    needs: [check-sensitive-step-1, check-sensitive-step-2, check-sensitive-step-3]
+    if: >
+      (github.event_name == 'workflow_dispatch' || github.event_name == 'push') ||
+      (needs.check-sensitive-step-2.outputs.do_build == 'true' || needs.check-sensitive-step-3.outputs.do_build == 'true')
     runs-on: [self-hosted]
     steps:
     - name: Checkout Code
diff --git a/.github/workflows/build_x86_64_npu.yaml b/.github/workflows/build_x86_64_npu.yaml
index 25766cab..08d6d589 100644
--- a/.github/workflows/build_x86_64_npu.yaml
+++ b/.github/workflows/build_x86_64_npu.yaml
@@ -18,8 +18,16 @@ on:
     branches: [main]
     types: [opened, synchronize, reopened]
     paths-ignore:
-      - '.github/**'
-      - 'cibuild/**'
+      - 'cmake/**'
+      - 'docs/**'
+      - 'third_party/**'
+      - 'tools/**'
+      - '*.md'
+      - '*.txt'
+      - '*.yml'
+  pull_request_review:
+    types: [submitted]
+    paths-ignore:
       - 'cmake/**'
       - 'docs/**'
       - 'third_party/**'
@@ -36,8 +44,128 @@ concurrency:
   cancel-in-progress: ${{ startsWith(github.ref, 'refs/pull/') }}
 
 jobs:
+  # need to review code first when sensitive files are modified.
+  check-sensitive-step-1:
+    runs-on: [self-hosted]
+    outputs:
+      should_check: ${{ steps.decide.outputs.should_check }}
+      approved: ${{ steps.decide.outputs.approved }}
+    steps:
+      - name: Decide whether to check sensitive file
+        id: decide
+        run: |
+          event="${{ github.event_name }}"
+          if [[ "$event" == "workflow_dispatch" || "$event" == "push" ]]; then
+            echo "ignore workflow_dispatch and push events in check-sensitive-step-1."
+            echo "should_check=false" >> $GITHUB_OUTPUT
+            echo "approved=false" >> $GITHUB_OUTPUT
+          elif [[ "$event" == "pull_request" ]]; then
+            echo "should_check=true" >> $GITHUB_OUTPUT
+            echo "approved=false" >> $GITHUB_OUTPUT
+          elif [[ "$event" == "pull_request_review" ]]; then
+            if [[ "${{ github.event.review.state }}" == "approved" ]]; then
+              echo "should_check=false" >> $GITHUB_OUTPUT
+              echo "approved=true" >> $GITHUB_OUTPUT
+            else
+              echo "should_check=false" >> $GITHUB_OUTPUT
+              echo "approved=false" >> $GITHUB_OUTPUT
+            fi
+          else
+            echo "should_check=false" >> $GITHUB_OUTPUT
+            echo "approved=false" >> $GITHUB_OUTPUT
+          fi
+
+  check-sensitive-step-2:
+    needs: check-sensitive-step-1
+    #if: >
+    #  needs.check-sensitive-step-1.outputs.should_check == 'true' &&
+    #  (github.event_name == 'pull_request' || github.event_name == 'pull_request_review')
+    if: >
+      needs.check-sensitive-step-1.outputs.should_check == 'true' && github.event_name == 'pull_request'
+    runs-on: [self-hosted]
+    outputs:
+      do_build: ${{ steps.check.outputs.do_build }}
+    steps:
+      - name: Checkout Code
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0  # Ensure we can compare commits
+
+      - name: Install jq
+        run: yum install -y jq
+
+      - name: Check if sensitive files were changed
+        id: check_sensitive
+        run: |
+          sensitive_files=(
+            ".github/**.yaml"
+            "cibuild/**.sh"
+            "setup.py"
+          )
+          changed_files=$(git diff --name-only ${{ github.event.pull_request.base.sha }} ${{ github.sha }})
+          requires_approval="false"
+          while IFS= read -r changed_file; do
+            [[ -z "$changed_file" ]] && continue
+            for pattern in "${sensitive_files[@]}"; do
+              if [[ "$changed_file" == $pattern ]]; then
+                requires_approval="true"
+                break 2
+              fi
+          done
+          done < <(git diff --name-only "${{ github.event.pull_request.base.sha }}" "${{ github.sha }}")
+
+          echo "requires_approval=$requires_approval" >> $GITHUB_OUTPUT
+
+      - name: Check PR approvals
+        id: check_approved
+        if: ${{ github.event_name == 'pull_request' && steps.check_sensitive.outputs.requires_approval == 'true' }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          pr_number=${{ github.event.pull_request.number }}
+          response=$(curl -s -H "Authorization: Bearer $GITHUB_TOKEN" \
+            -H "Accept: application/vnd.github.v3+json" \
+            "https://api.github.com/repos/${{ github.repository }}/pulls/$pr_number/reviews")
+          
+          if echo "$response" | jq -e '.[] | select(.state == "APPROVED")' > /dev/null; then
+            echo "approved=true" >> $GITHUB_OUTPUT
+          else
+            echo "approved=false" >> $GITHUB_OUTPUT
+          fi
+
+      - name: Final check
+        id: check
+        run: |
+          if [ "${{ steps.check_sensitive.outputs.requires_approval }}" != "true" ]; then
+            echo "do_build=true" >> $GITHUB_OUTPUT
+          elif [ "${{ steps.check_approved.outputs.approved }}" == "true" ]; then
+            echo "do_build=true" >> $GITHUB_OUTPUT
+          else
+            echo "do_build=false" >> $GITHUB_OUTPUT
+          fi
+
+  check-sensitive-step-3:
+    needs: check-sensitive-step-1
+    if: >
+      github.event_name == 'pull_request_review'
+    runs-on: [self-hosted]
+    outputs:
+      do_build: ${{ steps.check.outputs.do_build }}
+    steps:
+      - name: Checkout status
+        id: check
+        run:
+          if [ "${{ needs.check-sensitive-step-1.outputs.approved }}" == "true" ]; then
+            echo "do_build=true" >> $GITHUB_OUTPUT
+          else
+            echo "do_build=false" >> $GITHUB_OUTPUT
+          fi
+
   build:
-    if: ${{ github.event_name == 'workflow_dispatch' || github.event_name == 'push' || github.event_name == 'pull_request' }}
+    needs: [check-sensitive-step-1, check-sensitive-step-2, check-sensitive-step-3]
+    if: >
+      (github.event_name == 'workflow_dispatch' || github.event_name == 'push') ||
+      (needs.check-sensitive-step-2.outputs.do_build == 'true' || needs.check-sensitive-step-3.outputs.do_build == 'true')
     runs-on: [self-hosted]
     steps:
     - name: Checkout Code
diff --git a/xllm/api_service/chat_service_impl.cpp b/xllm/api_service/chat_service_impl.cpp
index 362304c6..f8923f89 100644
--- a/xllm/api_service/chat_service_impl.cpp
+++ b/xllm/api_service/chat_service_impl.cpp
@@ -54,6 +54,9 @@ ToolCallResult process_tool_calls(std::string text,
                                   google::protobuf::Arena* arena = nullptr) {
   ToolCallResult result;
 
+  /// --------------
+  LOG(ERROR) << "====================== test =======================";
+
   function_call::FunctionCallParser parser(tools, parser_format);
 
   if (!parser.has_tool_call(text)) {