diff --git a/pipelines/examples/mlx_pipeline.py b/pipelines/examples/mlx_pipeline.py
index 71faa4f..c8dcd4a 100644
--- a/pipelines/examples/mlx_pipeline.py
+++ b/pipelines/examples/mlx_pipeline.py
@@ -5,15 +5,17 @@ date: 2024-05-22
 version: 1.0
 license: MIT
 description: A pipeline for running the mlx-lm server with a specified model.
-dependencies: requests, mlx-lm
-environment_variables: MLX_MODEL
+dependencies: requests, mlx-lm, huggingface_hub
+environment_variables: MLX_MODEL, MLX_STOP, HUGGINGFACE_TOKEN
 """
 
 from typing import List, Union, Generator, Iterator
-import requests
 import subprocess
 import os
 import socket
+import time
+import requests
+from huggingface_hub import login
 from schemas import OpenAIChatMessage
 
 
@@ -23,21 +25,30 @@ class Pipeline:
         self.id = "mlx_pipeline"
         self.name = "MLX Pipeline"
         self.process = None
-        self.model = os.getenv(
-            "MLX_MODEL", "mistralai/Mistral-7B-Instruct-v0.2"
-        )  # Default model if not set in environment variable
+        self.model = os.getenv('MLX_MODEL', 'mistralai/Mistral-7B-Instruct-v0.2')  # Default model if not set in environment variable
         self.port = self.find_free_port()
-        self.stop_sequences = os.getenv(
-            "MLX_STOP", "[INST]"
-        )  # Stop sequences from environment variable
+        self.stop_sequences = os.getenv('MLX_STOP', '[INST]')  # Stop sequences from environment variable
+        self.hf_token = os.getenv('HUGGINGFACE_TOKEN', None)  # Hugging Face token from environment variable
+
+        # Authenticate with Hugging Face if a token is provided
+        if self.hf_token:
+            self.authenticate_huggingface(self.hf_token)
 
     @staticmethod
     def find_free_port():
         with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
-            s.bind(("", 0))
+            s.bind(('', 0))
             s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
             return s.getsockname()[1]
 
+    @staticmethod
+    def authenticate_huggingface(token: str):
+        try:
+            login(token)
+            print("Successfully authenticated with Hugging Face.")
+        except Exception as e:
+            print(f"Failed to authenticate with Hugging Face: {e}")
+
     async def on_startup(self):
         # This function is called when the server is started.
         print(f"on_startup:{__name__}")
@@ -54,13 +65,18 @@ class Pipeline:
             self.process = subprocess.Popen(
                 ["mlx_lm.server", "--model", self.model, "--port", str(self.port)],
                 stdout=subprocess.PIPE,
-                stderr=subprocess.PIPE,
-            )
-            print(
-                f"Subprocess started with PID: {self.process.pid} on port {self.port}"
+                stderr=subprocess.PIPE
             )
+            print(f"Subprocess started with PID: {self.process.pid} on port {self.port}")
+
+            # Check if the process has started correctly
+            time.sleep(2)  # Give it a moment to start
+            if self.process.poll() is not None:
+                raise RuntimeError(f"Subprocess failed to start. Return code: {self.process.returncode}")
+
         except Exception as e:
             print(f"Failed to start subprocess: {e}")
+            self.process = None
 
     def stop_subprocess(self):
         # Stop the subprocess if it is running
@@ -71,6 +87,8 @@ class Pipeline:
                 print(f"Subprocess with PID {self.process.pid} terminated")
             except Exception as e:
                 print(f"Failed to terminate subprocess: {e}")
+            finally:
+                self.process = None
 
     def get_response(
         self, user_message: str, messages: List[OpenAIChatMessage], body: dict
@@ -78,9 +96,15 @@ class Pipeline:
         # This is where you can add your custom pipelines like RAG.'
         print(f"get_response:{__name__}")
 
+        if not self.process or self.process.poll() is not None:
+            return "Error: Subprocess is not running."
+
         MLX_BASE_URL = f"http://localhost:{self.port}"
         MODEL = self.model
 
+        # Convert OpenAIChatMessage objects to dictionaries
+        messages_dict = [{"role": message.role, "content": message.content} for message in messages]
+
         # Extract additional parameters from the body
         temperature = body.get("temperature", 0.8)
         max_tokens = body.get("max_tokens", 1000)
@@ -96,12 +120,12 @@ class Pipeline:
 
         payload = {
             "model": MODEL,
-            "messages": [message.model_dump() for message in messages],
+            "messages": messages_dict,
             "temperature": temperature,
             "max_tokens": max_tokens,
             "top_p": top_p,
             "repetition_penalty": repetition_penalty,
-            "stop": stop,
+            "stop": stop
         }
 
         try:
@@ -115,4 +139,4 @@ class Pipeline:
 
             return r.iter_lines()
         except Exception as e:
-            return f"Error: {e}"
+            return f"Error: {e}"
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