diff --git a/demo-serving/op/ctr_prediction_op.cpp b/demo-serving/op/ctr_prediction_op.cpp
index 04a6cebf0d0da2171b2bf146cd3e9f0e49973fa9..541e03fd5f8302280c501b0a8a085f6d636faa89 100644
--- a/demo-serving/op/ctr_prediction_op.cpp
+++ b/demo-serving/op/ctr_prediction_op.cpp
@@ -14,6 +14,7 @@
 
 #include "demo-serving/op/ctr_prediction_op.h"
 #include <algorithm>
+#include <string>
 #include "predictor/framework/infer.h"
 #include "predictor/framework/memory.h"
 
@@ -27,31 +28,94 @@ using baidu::paddle_serving::predictor::ctr_prediction::Response;
 using baidu::paddle_serving::predictor::ctr_prediction::CTRReqInstance;
 using baidu::paddle_serving::predictor::ctr_prediction::Request;
 
-const int CTR_PREDICTION_INPUT_SLOTS =
-    27;  // Total 26 sparse input + 1 dense input
-const int CTR_PREDICTION_SPARSE_SLOTS = 26;  // First 26: sparse input
-const int CTR_PREDICTION_DENSE_SLOT = 26;    // Last 1: dense input
+// Total 26 sparse input + 1 dense input
+const int CTR_PREDICTION_INPUT_SLOTS = 27;
+
+// First 26: sparse input
+const int CTR_PREDICTION_SPARSE_SLOTS = 26;
+
+// Last 1: dense input
+const int CTR_PREDICTION_DENSE_SLOT_ID = 26;
+const int CTR_PREDICTION_DENSE_DIM = 13;
+const int CTR_PREDICTION_EMBEDDING_SIZE = 10;
+
+#if 1
+struct CubeValue {
+  int error;
+  std::string buff;
+};
+
+#endif
+void fill_response_with_message(Response *response,
+                                int err_code,
+                                std::string err_msg) {
+  if (response == NULL) {
+    LOG(ERROR) << "response is NULL";
+    return;
+  }
+
+  response->set_err_code(err_code);
+  response->set_err_msg(err_msg);
+  return;
+}
 
 int CTRPredictionOp::inference() {
   const Request *req = dynamic_cast<const Request *>(get_request_message());
 
   TensorVector *in = butil::get_object<TensorVector>();
+  Response *res = mutable_data<Response>();
+
   uint32_t sample_size = req->instances_size();
   if (sample_size <= 0) {
     LOG(WARNING) << "No instances need to inference!";
+    fill_response_with_message(res, -1, "Sample size invalid");
     return -1;
   }
 
   paddle::PaddleTensor lod_tensors[CTR_PREDICTION_INPUT_SLOTS];
-  for (int i = 0; i < CTR_PREDICTION_INPUT_SLOTS; ++i) {
+  for (int i = 0; i < CTR_PREDICTION_SPARSE_SLOTS; ++i) {
     lod_tensors[i].dtype = paddle::PaddleDType::FLOAT32;
     std::vector<std::vector<size_t>> &lod = lod_tensors[i].lod;
     lod.resize(1);
     lod[0].push_back(0);
   }
 
-  lot_tensors[CTR_PREDICTION_SPARSE_SLOTS].dtype = paddle::PaddleDType::INT64;
+  // Query cube API for sparse embeddings
+  std::vector<int64_t> keys;
+  std::vector<CubeValue> values;
+
+  for (uint32_t si = 0; si < sample_size; ++si) {
+    const CTRReqInstance &req_instance = req->instances(si);
+    if (req_instance.sparse_ids_size() != CTR_PREDICTION_DENSE_DIM) {
+      std::ostringstream iss;
+      iss << "dense input size != " << CTR_PREDICTION_DENSE_DIM;
+      fill_response_with_message(res, -1, iss.str());
+      return -1;
+    }
+
+    for (int i = 0; i < req_instance.sparse_ids_size(); ++i) {
+      keys.push_back(req_instance.sparse_ids(i));
+    }
+  }
+
+#if 0
+  mCube::CubeAPI* cube = CubeAPI::instance();
+  int ret = cube->seek(keys, values);
+  if (ret != 0) {
+    fill_response_with_message(res, -1, "Query cube for embeddings error");
+    LOG(ERROR) << "Query cube for embeddings error";
+    return -1;
+  }
+#else
+  float buff[CTR_PREDICTION_EMBEDDING_SIZE] = {
+      0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.00};
+  for (int i = 0; i < keys.size(); ++i) {
+    values[i].error = 0;
+    values[i].buff = std::string(reinterpret_cast<char *>(buff), sizeof(buff));
+  }
+#endif
 
+  // Sparse embeddings
   for (int i = 0; i < CTR_PREDICTION_SPARSE_SLOTS; ++i) {
     paddle::PaddleTensor lod_tensor = lod_tensors[i];
     std::vector<std::vector<size_t>> &lod = lod_tensor.lod;
@@ -61,31 +125,48 @@ int CTRPredictionOp::inference() {
       lod[0].push_back(lod[0].back() + 1);
     }
 
-    lod_tensor.shape = {lod[0].back(), 1};
-    lod_tensor.data.Resize(lod[0].back() * sizeof(int64_t));
+    lod_tensor.shape = {lod[0].back(), CTR_PREDICTION_EMBEDDING_SIZE};
+    lod_tensor.data.Resize(lod[0].back() * sizeof(float) *
+                           CTR_PREDICTION_EMBEDDING_SIZE);
 
     int offset = 0;
     for (uint32_t si = 0; si < sample_size; ++si) {
-      int64_t *data_ptr =
-          static_cast<int64_t *>(lod_tensor.data.data()) + offset;
+      float *data_ptr = static_cast<float *>(lod_tensor.data.data()) + offset;
       const CTRReqInstance &req_instance = req->instances(si);
-      int id_count = 1;
-      memcpy(data_ptr, &req_instance.sparse_ids().data()[i], sizeof(int64_t));
-      offset += 1;
+
+      int idx = si * CTR_PREDICTION_SPARSE_SLOTS + i;
+      if (values[idx].buff.size() !=
+          sizeof(float) * CTR_PREDICTION_EMBEDDING_SIZE) {
+        LOG(ERROR) << "Embedding vector size not expected";
+        fill_response_with_message(
+            res, -1, "Embedding vector size not expected");
+        return -1;
+      }
+
+      memcpy(data_ptr, values[idx].buff.data(), values[idx].buff.size());
+      offset += CTR_PREDICTION_EMBEDDING_SIZE;
     }
 
     in->push_back(lod_tensor);
   }
 
-  paddle::PaddleTensor lod_tensor = lod_tensors[CTR_PREDICTION_DENSE_SLOT];
+  // Dense features
+  paddle::PaddleTensor lod_tensor = lod_tensors[CTR_PREDICTION_DENSE_SLOT_ID];
+  lod_tensor.dtype = paddle::PaddleDType::INT64;
   std::vector<std::vector<size_t>> &lod = lod_tensor.lod;
 
   for (uint32_t si = 0; si < sample_size; ++si) {
     const CTRReqInstance &req_instance = req->instances(si);
+    if (req_instance.dense_ids_size() != CTR_PREDICTION_DENSE_DIM) {
+      std::ostringstream iss;
+      iss << "dense input size != " << CTR_PREDICTION_DENSE_DIM;
+      fill_response_with_message(res, -1, iss.str());
+      return -1;
+    }
     lod[0].push_back(lod[0].back() + req_instance.dense_ids_size());
   }
 
-  lod_tensor.shape = {lod[0].back(), 1};
+  lod_tensor.shape = {lod[0].back(), CTR_PREDICTION_DENSE_DIM};
   lod_tensor.data.Resize(lod[0].back() * sizeof(int64_t));
 
   int offset = 0;
@@ -94,7 +175,7 @@ int CTRPredictionOp::inference() {
     const CTRReqInstance &req_instance = req->instances(si);
     int id_count = req_instance.dense_ids_size();
     memcpy(data_ptr,
-           req_instance.ids().data(),
+           req_instance.dense_ids().data(),
            sizeof(int64_t) * req_instance.dense_ids_size());
     offset += req_instance.dense_ids_size();
   }
@@ -104,6 +185,7 @@ int CTRPredictionOp::inference() {
   TensorVector *out = butil::get_object<TensorVector>();
   if (!out) {
     LOG(ERROR) << "Failed get tls output object";
+    fill_response_with_message(res, -1, "Failed get thread local resource");
     return -1;
   }
 
@@ -112,22 +194,23 @@ int CTRPredictionOp::inference() {
           CTR_PREDICTION_MODEL_NAME, in, out, sample_size)) {
     LOG(ERROR) << "Failed do infer in fluid model: "
                << CTR_PREDICTION_MODEL_NAME;
+    fill_response_with_message(res, -1, "Failed do infer in fluid model");
     return -1;
   }
 
   if (out->size() != in->size()) {
     LOG(ERROR) << "Output tensor size not equal that of input";
+    fill_response_with_message(res, -1, "Output size != input size");
     return -1;
   }
 
-  Response *res = mutable_data<Response>();
-
   for (size_t i = 0; i < out->size(); ++i) {
     int dim1 = out->at(i).shape[0];
     int dim2 = out->at(i).shape[1];
 
     if (out->at(i).dtype != paddle::PaddleDType::FLOAT32) {
       LOG(ERROR) << "Expected data type float";
+      fill_response_with_message(res, -1, "Expected data type float");
       return -1;
     }
 
@@ -150,6 +233,9 @@ int CTRPredictionOp::inference() {
   }
   out->clear();
   butil::return_object<TensorVector>(out);
+
+  res->set_err_code(0);
+  res->set_err_msg(std::string(""));
   return 0;
 }
 
diff --git a/demo-serving/proto/CMakeLists.txt b/demo-serving/proto/CMakeLists.txt
index 2edd5e9eacde35b2add7fd11f676662e4c218e45..1790f1d6e770475a17532424022c819d3ba6cd49 100644
--- a/demo-serving/proto/CMakeLists.txt
+++ b/demo-serving/proto/CMakeLists.txt
@@ -6,6 +6,7 @@ LIST(APPEND protofiles
         ${CMAKE_CURRENT_LIST_DIR}/echo_kvdb_service.proto
         ${CMAKE_CURRENT_LIST_DIR}/int64tensor_service.proto
         ${CMAKE_CURRENT_LIST_DIR}/text_classification.proto
+        ${CMAKE_CURRENT_LIST_DIR}/ctr_prediction.proto
 )
 
 PROTOBUF_GENERATE_SERVING_CPP(TRUE PROTO_SRCS PROTO_HDRS ${protofiles})
diff --git a/demo-serving/proto/ctr_prediction.proto b/demo-serving/proto/ctr_prediction.proto
index 8efed93c698b9f3d3e63c0233994b29bb312bc81..ad1ccb06652dee6e027fdbe73eaa18f91ffefbe3 100644
--- a/demo-serving/proto/ctr_prediction.proto
+++ b/demo-serving/proto/ctr_prediction.proto
@@ -31,7 +31,11 @@ message CTRResInstance {
   required float prob1 = 2;
 };
 
-message Response { repeated CTRResInstance predictions = 1; };
+message Response {
+  repeated CTRResInstance predictions = 1;
+  required int64 err_code = 2;
+  optional string err_msg = 3;
+};
 
 service CTRPredictionService {
   rpc inference(Request) returns (Response);