diff --git a/mcp-client-python/client.py b/mcp-client-python/client.py
index c53b39b..389b0d7 100644
--- a/mcp-client-python/client.py
+++ b/mcp-client-python/client.py
@@ -64,7 +64,7 @@ class MCPClient:
 
         # Initial Claude API call
         response = self.anthropic.messages.create(
-            model="claude-sonnet-4-0",
+            model="claude-sonnet-4-5",
             max_tokens=1000,
             messages=messages,
             tools=available_tools
@@ -97,7 +97,7 @@ class MCPClient:
 
                 # Get next response from Claude
                 response = self.anthropic.messages.create(
-                    model="claude-sonnet-4-0",
+                    model="claude-sonnet-4-5",
                     max_tokens=1000,
                     messages=messages,
                 )