diff --git a/python/packages/core/agent_framework/azure/_chat_client.py b/python/packages/core/agent_framework/azure/_chat_client.py
index b4bd3659ed..f07254b489 100644
--- a/python/packages/core/agent_framework/azure/_chat_client.py
+++ b/python/packages/core/agent_framework/azure/_chat_client.py
@@ -282,6 +282,23 @@ class MyOptions(AzureOpenAIChatOptions, total=False):
             **kwargs,
         )
 
+    @staticmethod
+    def get_web_search_tool(
+        *,
+        web_search_options: Any | None = None,
+    ) -> dict[str, Any]:
+        """Web search is not supported by Azure OpenAI's Chat Completions API.
+
+        Use ``OpenAIChatClient`` or ``AzureOpenAIResponsesClient`` for web search support.
+
+        Raises:
+            NotImplementedError: Always, since Azure OpenAI does not support web search.
+        """
+        raise NotImplementedError(
+            "Web search is not supported by Azure OpenAI's Chat Completions API. "
+            "Use OpenAIChatClient or AzureOpenAIResponsesClient for web search support."
+        )
+
     @override
     def _parse_text_from_openai(self, choice: Choice | ChunkChoice) -> Content | None:
         """Parse the choice into a Content object with type='text'.
diff --git a/python/packages/core/tests/azure/test_azure_chat_client.py b/python/packages/core/tests/azure/test_azure_chat_client.py
index 3e88504493..aa1828f54d 100644
--- a/python/packages/core/tests/azure/test_azure_chat_client.py
+++ b/python/packages/core/tests/azure/test_azure_chat_client.py
@@ -884,3 +884,12 @@ async def test_azure_chat_client_agent_level_tool_persistence():
         assert second_response.text is not None
         # Should use the agent-level weather tool again
         assert any(term in second_response.text.lower() for term in ["miami", "sunny", "72"])
+
+
+def test_get_web_search_tool_raises_not_implemented() -> None:
+    """Test that get_web_search_tool() raises NotImplementedError on Azure OpenAI.
+
+    Regression test for: https://github.com/microsoft/agent-framework/issues/3629
+    """
+    with pytest.raises(NotImplementedError, match="not supported by Azure OpenAI"):
+        AzureOpenAIChatClient.get_web_search_tool()