diff --git a/speechserving/speechserving/conf/application.yaml b/speechserving/speechserving/conf/application.yaml
index 8c4d9bc62d2ca4dac2676c48ca7154e85e414c35..c8d71f2f6ad816e9848096e84c637c0069757594 100644
--- a/speechserving/speechserving/conf/application.yaml
+++ b/speechserving/speechserving/conf/application.yaml
@@ -10,6 +10,8 @@ port: 8090
 #                     CONFIG FILE                                #
 ##################################################################
 # add engine type (Options: asr, tts) and config file here.
+
 engine_backend:
     asr: 'conf/asr/asr.yaml'
     tts: 'conf/tts/tts.yaml'
+
diff --git a/speechserving/speechserving/conf/asr/asr.yaml b/speechserving/speechserving/conf/asr/asr.yaml
index 39df2548771517f2bd4ee3764516b7aec50375b1..4c3b0a67e30273681fe765fc2e827f86a21ac380 100644
--- a/speechserving/speechserving/conf/asr/asr.yaml
+++ b/speechserving/speechserving/conf/asr/asr.yaml
@@ -1,7 +1,7 @@
 model: 'conformer_wenetspeech'
 lang: 'zh'
 sample_rate: 16000
-cfg_path: "/home/users/zhangyinhui/.paddlespeech/models/conformer_wenetspeech-zh-16k/asr1_conformer_wenetspeech_ckpt_0.1.1.model.tar/model.yaml"
-ckpt_path: "/home/users/zhangyinhui/.paddlespeech/models/conformer_wenetspeech-zh-16k/asr1_conformer_wenetspeech_ckpt_0.1.1.model.tar/exp/conformer/checkpoints/wenetspeech"
+cfg_path: 
+ckpt_path: 
 decode_method: 'attention_rescoring'
 force_yes: False
diff --git a/speechserving/speechserving/engine/asr/python/asr_engine.py b/speechserving/speechserving/engine/asr/python/asr_engine.py
index bb1596af44de1dd849b64eefeee020d8b4df5f17..e8289332167bf6cb31db08de54c66860f7504522 100644
--- a/speechserving/speechserving/engine/asr/python/asr_engine.py
+++ b/speechserving/speechserving/engine/asr/python/asr_engine.py
@@ -11,23 +11,23 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-import paddle
 import io
-import soundfile
 import os
-import librosa
 from typing import List
 from typing import Optional
 from typing import Union
 
-from paddlespeech.cli.log import logger
+import librosa
+import paddle
+import soundfile
+from engine.base_engine import BaseEngine
+
 from paddlespeech.cli.asr.infer import ASRExecutor
+from paddlespeech.cli.log import logger
 from paddlespeech.s2t.frontend.featurizer.text_featurizer import TextFeaturizer
 from paddlespeech.s2t.transform.transformation import Transformation
 from paddlespeech.s2t.utils.dynamic_import import dynamic_import
 from paddlespeech.s2t.utils.utility import UpdateConfig
-
-from engine.base_engine import BaseEngine
 from utils.config import get_config
 
 __all__ = ['ASREngine']
@@ -141,42 +141,55 @@ class ASREngine(BaseEngine):
     Args:
         metaclass: Defaults to Singleton.
     """
+
     def __init__(self):
         super(ASREngine, self).__init__()
 
-    def init(self, config_file: str):
+    def init(self, config_file: str) -> bool:
+        """init engine resource
+
+        Args:
+            config_file (str): config file
 
+        Returns:
+            bool: init failed or success
+        """
+        self.input = None
+        self.output = None
         self.executor = ASRServerExecutor()
-        self.config = get_config(config_file)
 
-        paddle.set_device(paddle.get_device())
-        self.executor._init_from_path(
-            self.config.model,
-            self.config.lang,
-            self.config.sample_rate,
-            self.config.cfg_path,
-            self.config.decode_method,
-            self.config.ckpt_path)
+        try:
+            self.config = get_config(config_file)
+            paddle.set_device(paddle.get_device())
+            self.executor._init_from_path(
+                self.config.model, self.config.lang, self.config.sample_rate,
+                self.config.cfg_path, self.config.decode_method,
+                self.config.ckpt_path)
+        except:
+            logger.info("Initialize ASR server engine Failed.")
+            return False
 
         logger.info("Initialize ASR server engine successfully.")
-
-        self.input = None
-        self.output = None
+        return True
 
     def run(self, audio_data):
+        """engine run 
 
-        if self.executor._check(io.BytesIO(audio_data), self.config.sample_rate, self.config.force_yes):
+        Args:
+            audio_data (bytes): base64.b64decode
+        """
+        if self.executor._check(
+                io.BytesIO(audio_data), self.config.sample_rate,
+                self.config.force_yes):
+            logger.info("start run asr engine")
             self.executor.preprocess(self.config.model, io.BytesIO(audio_data))
             self.executor.infer(self.config.model)
-            self.output = self.executor.postprocess()   # Retrieve result of asr.
+            self.output = self.executor.postprocess()  # Retrieve result of asr.
         else:
             logger.info("file check failed!")
-
-        logger.info("start run asr engine")
+            self.output = None
 
     def postprocess(self):
-        
+        """postprocess
+        """
         return self.output
-
-
-
diff --git a/speechserving/speechserving/engine/base_engine.py b/speechserving/speechserving/engine/base_engine.py
index 36048dcc69be87585c2460542350df39d2679f85..0cc20209479ea7e033943b799a7e161ac21e3b35 100644
--- a/speechserving/speechserving/engine/base_engine.py
+++ b/speechserving/speechserving/engine/base_engine.py
@@ -18,6 +18,8 @@ from typing import Union
 
 from pattern_singleton import Singleton
 
+__all__ = ['BaseEngine']
+
 
 class BaseEngine(metaclass=Singleton):
     """
diff --git a/speechserving/speechserving/engine/engine_factory.py b/speechserving/speechserving/engine/engine_factory.py
index 336a9a6f8b007c5f9687f9c3547a450159c86c86..2b9f9db70d1712cc681e5d0068304915c7479c7a 100644
--- a/speechserving/speechserving/engine/engine_factory.py
+++ b/speechserving/speechserving/engine/engine_factory.py
@@ -14,10 +14,12 @@
 from engine.asr.python.asr_engine import ASREngine
 from engine.tts.python.tts_engine import TTSEngine
 
+__all__ = ['EngineFactory']
+
 
 class EngineFactory(object):
     @staticmethod
-    def get_engine(engine_name):
+    def get_engine(engine_name: str):
         if engine_name == 'asr':
             return ASREngine()
         elif engine_name == 'tts':
diff --git a/speechserving/speechserving/main.py b/speechserving/speechserving/main.py
index 3b367418f28d53e773bbddf8ff61d1c03ca5a366..6d4891c7dcb3e7a732efd09d97417d4ad115f21e 100644
--- a/speechserving/speechserving/main.py
+++ b/speechserving/speechserving/main.py
@@ -12,21 +12,28 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import argparse
+
 import uvicorn
 import yaml
+from engine.engine_factory import EngineFactory
 from fastapi import FastAPI
-
 from restful.api import setup_router
-from utils.log import logger
+
 from utils.config import get_config
-from engine.engine_factory import EngineFactory
+from utils.log import logger
 
 app = FastAPI(
     title="PaddleSpeech Serving API", description="Api", version="0.0.1")
 
 
 def init(config):
-    """ system initialization
+    """system initialization
+
+    Args:
+        config (CfgNode): config object
+
+    Returns:
+        bool: 
     """
     # init api
     api_list = list(config.engine_backend)
@@ -34,10 +41,11 @@ def init(config):
     app.include_router(api_router)
 
     # init engine
-    engine_list = []
+    engine_pool = []
     for engine in config.engine_backend:
-        engine_list.append(EngineFactory.get_engine(engine_name=engine))
-        engine_list[-1].init(config_file=config.engine_backend[engine])
+        engine_pool.append(EngineFactory.get_engine(engine_name=engine))
+        if not engine_pool[-1].init(config_file=config.engine_backend[engine]):
+            return False
 
     return True
 
diff --git a/speechserving/speechserving/restful/api.py b/speechserving/speechserving/restful/api.py
index c5539f2431027a19e267974599dbd42a1ee58162..bdff935ac977dcff4e14a9dee9d1c030a6581562 100644
--- a/speechserving/speechserving/restful/api.py
+++ b/speechserving/speechserving/restful/api.py
@@ -12,13 +12,15 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 from typing import List
+
 from fastapi import APIRouter
 
-from .tts_api import router as tts_router
 from .asr_api import router as asr_router
+from .tts_api import router as tts_router
 
 _router = APIRouter()
 
+
 def setup_router(api_list: List):
 
     for api_name in api_list:
@@ -30,4 +32,3 @@ def setup_router(api_list: List):
             pass
 
     return _router
-
diff --git a/speechserving/speechserving/restful/asr_api.py b/speechserving/speechserving/restful/asr_api.py
index ab2c8048af4f1e00caeb5ac3c7ed2037be79e962..6ac647bc9a67a9b31dbcf1f8a80539a1a22f6bee 100644
--- a/speechserving/speechserving/restful/asr_api.py
+++ b/speechserving/speechserving/restful/asr_api.py
@@ -11,16 +11,23 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from fastapi import APIRouter
 import base64
+import traceback
+from typing import Union
 
 from engine.asr.python.asr_engine import ASREngine
-from .response import ASRResponse
-from .request import ASRRequest
+from fastapi import APIRouter
 
+from .request import ASRRequest
+from .response import ASRResponse
+from .response import ErrorResponse
+from utils.errors import ErrorCode
+from utils.errors import failed_response
+from utils.exception import ServerBaseException
 
 router = APIRouter()
 
+
 @router.get('/paddlespeech/asr/help')
 def help():
     """help
@@ -28,10 +35,23 @@ def help():
     Returns:
         json: [description]
     """
-    return {'hello': 'world'}
+    response = {
+        "success": "True",
+        "code": 200,
+        "message": {
+            "global": "success"
+        },
+        "result": {
+            "description": "tts server",
+            "input": "base64 string of wavfile",
+            "output": "transcription"
+        }
+    }
+    return response
 
 
-@router.post("/paddlespeech/asr", response_model=ASRResponse)
+@router.post(
+    "/paddlespeech/asr", response_model=Union[ASRResponse, ErrorResponse])
 def asr(request_body: ASRRequest):
     """asr api 
 
@@ -41,21 +61,28 @@ def asr(request_body: ASRRequest):
     Returns:
         json: [description]
     """
-    audio_data = base64.b64decode(request_body.audio)
-    # single 
-    asr_engine = ASREngine()
-    asr_engine.run(audio_data)
-    asr_results = asr_engine.postprocess()
-
-    json_body = {
-                    "success": True,
-                    "code": 0,
-                    "message": {
-                        "description": "success" 
-                    },
-                    "result": {
-                        "transcription": asr_results
-                    }
-                }
-
-    return json_body
+    try:
+        # single 
+        audio_data = base64.b64decode(request_body.audio)
+        asr_engine = ASREngine()
+        asr_engine.run(audio_data)
+        asr_results = asr_engine.postprocess()
+
+        response = {
+            "success": True,
+            "code": 200,
+            "message": {
+                "description": "success"
+            },
+            "result": {
+                "transcription": asr_results
+            }
+        }
+
+    except ServerBaseException as e:
+        response = failed_response(e.error_code, e.msg)
+    except:
+        response = failed_response(ErrorCode.SERVER_UNKOWN_ERR)
+        traceback.print_exc()
+
+    return response
diff --git a/speechserving/speechserving/restful/request.py b/speechserving/speechserving/restful/request.py
index 9ebc6d752aaee8dc5897091593a3a8c5a6e88511..2be5f0e546dee6c1c042820ac1a3838a446e23ea 100644
--- a/speechserving/speechserving/restful/request.py
+++ b/speechserving/speechserving/restful/request.py
@@ -19,7 +19,6 @@ from pydantic import BaseModel
 __all__ = ['ASRRequest', 'TTSRequest']
 
 
-
 #****************************************************************************************/
 #************************************ ASR request ***************************************/
 #****************************************************************************************/
@@ -31,14 +30,14 @@ class ASRRequest(BaseModel):
         "audio_format": "wav",
         "sample_rate": 16000,
         "lang": "zh_cn",
-        "ptt":false
+        "punc":false
     }
     """
     audio: str
     audio_format: str
     sample_rate: int
     lang: str
-    ptt: Optional[bool] = None
+    punc: Optional[bool] = None
 
 
 #****************************************************************************************/
diff --git a/speechserving/speechserving/restful/response.py b/speechserving/speechserving/restful/response.py
index db24f5310b18609a5ef3d330cb7b6641d62af41d..ab5e395ba6914482e320d13abf2744e2fef71ec0 100644
--- a/speechserving/speechserving/restful/response.py
+++ b/speechserving/speechserving/restful/response.py
@@ -86,3 +86,22 @@ class TTSResponse(BaseModel):
     code: int
     message: Message
     result: TTSResult
+
+
+#****************************************************************************************/
+#********************************** Error response **************************************/
+#****************************************************************************************/
+class ErrorResponse(BaseModel):
+    """
+    response example
+    {
+        "success": false,
+        "code": 0,
+        "message": {
+            "description": "Unknown error occurred."
+        }
+    }
+    """
+    success: bool
+    code: int
+    message: Message
diff --git a/speechserving/speechserving/restful/tts_api.py b/speechserving/speechserving/restful/tts_api.py
index e9dcfa16fa17e736b8ee79fbd8ee170a6fcacc0a..a160e31dc1abc8d16cc2ff99a6a3db3f37296fe5 100644
--- a/speechserving/speechserving/restful/tts_api.py
+++ b/speechserving/speechserving/restful/tts_api.py
@@ -12,11 +12,13 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import traceback
+from typing import Union
 
 from engine.tts.python.tts_engine import TTSEngine
 from fastapi import APIRouter
 
 from .request import TTSRequest
+from .response import ErrorResponse
 from .response import TTSResponse
 from utils.errors import ErrorCode
 from utils.errors import failed_response
@@ -47,7 +49,8 @@ def help():
     return response
 
 
-@router.post("/paddlespeech/tts", response_model=TTSResponse)
+@router.post(
+    "/paddlespeech/tts", response_model=Union[TTSResponse, ErrorResponse])
 def tts(request_body: TTSRequest):
     """tts api
 
diff --git a/speechserving/speechserving/utils/__init__.py b/speechserving/speechserving/utils/__init__.py
index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..97043fd7ba6885aac81cad5a49924c23c67d4d47 100644
--- a/speechserving/speechserving/utils/__init__.py
+++ b/speechserving/speechserving/utils/__init__.py
@@ -0,0 +1,13 @@
+# Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
diff --git a/speechserving/speechserving/utils/config.py b/speechserving/speechserving/utils/config.py
index 513c16f66c4bab0eab5885c601a4f44b94b8ba28..8c75f536f5de654f1a09fa82187cfef4ef442e90 100644
--- a/speechserving/speechserving/utils/config.py
+++ b/speechserving/speechserving/utils/config.py
@@ -15,7 +15,7 @@ import yaml
 from yacs.config import CfgNode
 
 
-def get_config(config_file):
+def get_config(config_file: str):
     """[summary]
 
     Args:
diff --git a/speechserving/speechserving/utils/errors.py b/speechserving/speechserving/utils/errors.py
index aa858cb083ad8476af35a742f0d4376c5ac13417..17ff75512cd447648ecedf9238809a42743b708c 100644
--- a/speechserving/speechserving/utils/errors.py
+++ b/speechserving/speechserving/utils/errors.py
@@ -52,6 +52,6 @@ def failed_response(code, msg=""):
     if not msg:
         msg = ErrorMsg.get(code, "Unknown error occurred.")
 
-    res = {"success": False, "code": int(code), "message": {"global": msg}}
+    res = {"success": False, "code": int(code), "message": {"description": msg}}
 
     return Response(content=json.dumps(res), media_type="application/json")
diff --git a/speechserving/speechserving/utils/util.py b/speechserving/speechserving/utils/util.py
index cf56857213cec7f922203fe32d079c8f80bd9611..e9104fa2d56283c48304d4676fae19e8dccd1ba5 100644
--- a/speechserving/speechserving/utils/util.py
+++ b/speechserving/speechserving/utils/util.py
@@ -13,7 +13,7 @@
 import base64
 
 
-def wav2base64(wav_file):
+def wav2base64(wav_file: str):
     """
     read wave file and covert to base64 string
     """
@@ -23,12 +23,10 @@ def wav2base64(wav_file):
     return base64_string
 
 
-def base64towav(base64_string):
+def base64towav(base64_string: str):
     pass
 
 
-
-
 def self_check():
     """ self check resource
     """