diff --git a/core/src/org/labkey/core/mpc/McpServiceImpl.java b/core/src/org/labkey/core/mpc/McpServiceImpl.java
index c79b8d64dd7..c780f311e63 100644
--- a/core/src/org/labkey/core/mpc/McpServiceImpl.java
+++ b/core/src/org/labkey/core/mpc/McpServiceImpl.java
@@ -41,6 +41,7 @@
 import org.springframework.ai.openai.OpenAiEmbeddingOptions;
 import org.springframework.ai.openai.api.OpenAiApi;
 import org.springframework.ai.document.MetadataMode;
+import org.springframework.ai.anthropic.api.AnthropicApi;
 import org.springframework.ai.chat.client.ChatClient;
 import org.springframework.ai.chat.client.advisor.MessageChatMemoryAdvisor;
 import org.springframework.ai.chat.client.advisor.api.Advisor;
@@ -737,7 +738,7 @@ class _ClaudeProvider implements _ModelProvider
         @Override
         public String getModel()
         {
-            return "claude-3-5-sonnet-20241022";
+            return "claude-sonnet-4-5-20250929";
         }
 
         @Override
@@ -760,9 +761,11 @@ public AnthropicChatOptions getChatOptions()
         public AnthropicChatModel getChatModel()
         {
             AnthropicChatOptions chatOptions = getChatOptions();
-
+            AnthropicApi api = AnthropicApi.builder()
+                    .apiKey(System.getenv("CLAUDE_API_KEY"))
+                    .build();
             AnthropicChatModel chatModel = AnthropicChatModel.builder()
-                    .defaultOptions(chatOptions)
+                    .anthropicApi(api)
                     .build();
             return chatModel;
         }