fix(azure): stop mutating and corrupting caller messages in content rewrite (#5731)

mem0/llms/azure_openai.py

@@ -1,3 +1,4 @@
+import copy
 import json
 import os
 from typing import Dict, List, Optional, Union
@@ -69,6 +70,26 @@ class AzureOpenAILLM(LLMBase):
             default_headers=default_headers,
         )
 
+    @staticmethod
+    def _rewrite_assistant_keyword(messages):
+        """
+        Return a copy of ``messages`` with the word "assistant" replaced by "ai"
+        in the last message's textual content.
+
+        Azure's content management policy can flag the literal word "assistant",
+        which makes ``add`` fail (see issue #2636). The rewrite targets that
+        trigger without mutating the caller's messages and without assuming the
+        content is a string, so multimodal (list) content passes through untouched.
+        """
+        if not messages:
+            return messages
+
+        messages = copy.deepcopy(messages)
+        last_content = messages[-1].get("content")
+        if isinstance(last_content, str):
+            messages[-1]["content"] = last_content.replace("assistant", "ai")
+        return messages
+
     def _parse_response(self, response, tools):
         """
         Process the response based on whether tools are used or not.
@@ -121,11 +142,11 @@ class AzureOpenAILLM(LLMBase):
             str: The generated response.
         """
 
-        user_prompt = messages[-1]["content"]
+        # Azure's "Indirect Attacks" content filter can flag the literal word
-
+        # "assistant" in the prompt, so it is rewritten to "ai" before the request.
-        user_prompt = user_prompt.replace("assistant", "ai")
+        # Work on a copy so the caller's messages are left untouched and string-only
-
+        # content is handled without breaking multimodal (list) content.
-        messages[-1]["content"] = user_prompt
+        messages = self._rewrite_assistant_keyword(messages)
 
         params = self._get_supported_params(messages=messages, **kwargs)
 

mem0/llms/azure_openai_structured.py

@@ -1,3 +1,4 @@
+import copy
 import json
 import os
 from typing import Dict, List, Optional
@@ -66,11 +67,11 @@ class AzureOpenAIStructuredLLM(LLMBase):
             str: The generated response.
         """
 
-        user_prompt = messages[-1]["content"]
+        # Azure's "Indirect Attacks" content filter can flag the literal word
-
+        # "assistant" in the prompt, so it is rewritten to "ai" before the request.
-        user_prompt = user_prompt.replace("assistant", "ai")
+        # Work on a copy so the caller's messages are left untouched and string-only
-
+        # content is handled without breaking multimodal (list) content.
-        messages[-1]["content"] = user_prompt
+        messages = self._rewrite_assistant_keyword(messages)
 
         is_reasoning = self._is_reasoning_model(self.config.model)
         params = {
@@ -101,6 +102,26 @@ class AzureOpenAIStructuredLLM(LLMBase):
         response = self.client.chat.completions.create(**params)
         return self._parse_response(response, tools)
 
+    @staticmethod
+    def _rewrite_assistant_keyword(messages):
+        """
+        Return a copy of ``messages`` with the word "assistant" replaced by "ai"
+        in the last message's textual content.
+
+        Azure's content management policy can flag the literal word "assistant",
+        which makes ``add`` fail (see issue #2636). The rewrite targets that
+        trigger without mutating the caller's messages and without assuming the
+        content is a string, so multimodal (list) content passes through untouched.
+        """
+        if not messages:
+            return messages
+
+        messages = copy.deepcopy(messages)
+        last_content = messages[-1].get("content")
+        if isinstance(last_content, str):
+            messages[-1]["content"] = last_content.replace("assistant", "ai")
+        return messages
+
     def _parse_response(self, response, tools):
         """
         Process the response based on whether tools are used or not.

tests/llms/test_azure_openai.py

@@ -135,6 +135,52 @@ def test_generate_response_without_response_format(mock_openai_client):
     assert response == "Why did the chicken cross the road?"
 
 
+def test_generate_response_does_not_mutate_caller_messages(mock_openai_client):
+    config = AzureOpenAIConfig(model=MODEL, temperature=TEMPERATURE, max_tokens=MAX_TOKENS, top_p=TOP_P)
+    llm = AzureOpenAILLM(config)
+    messages = [{"role": "user", "content": "my assistant helps me schedule meetings"}]
+
+    mock_response = Mock()
+    mock_response.choices = [Mock(message=Mock(content="ok"))]
+    mock_openai_client.chat.completions.create.return_value = mock_response
+
+    llm.generate_response(messages)
+
+    assert messages[-1]["content"] == "my assistant helps me schedule meetings"
+
+
+def test_generate_response_rewrites_assistant_keyword_for_model_only(mock_openai_client):
+    config = AzureOpenAIConfig(model=MODEL, temperature=TEMPERATURE, max_tokens=MAX_TOKENS, top_p=TOP_P)
+    llm = AzureOpenAILLM(config)
+    messages = [{"role": "user", "content": "my assistant helps me"}]
+
+    mock_response = Mock()
+    mock_response.choices = [Mock(message=Mock(content="ok"))]
+    mock_openai_client.chat.completions.create.return_value = mock_response
+
+    llm.generate_response(messages)
+
+    sent_messages = mock_openai_client.chat.completions.create.call_args[1]["messages"]
+    assert sent_messages[-1]["content"] == "my ai helps me"
+    assert messages[-1]["content"] == "my assistant helps me"
+
+
+def test_generate_response_handles_multimodal_content(mock_openai_client):
+    config = AzureOpenAIConfig(model=MODEL, temperature=TEMPERATURE, max_tokens=MAX_TOKENS, top_p=TOP_P)
+    llm = AzureOpenAILLM(config)
+    messages = [{"role": "user", "content": [{"type": "text", "text": "describe my assistant"}]}]
+
+    mock_response = Mock()
+    mock_response.choices = [Mock(message=Mock(content="ok"))]
+    mock_openai_client.chat.completions.create.return_value = mock_response
+
+    response = llm.generate_response(messages)
+
+    assert response == "ok"
+    sent_messages = mock_openai_client.chat.completions.create.call_args[1]["messages"]
+    assert sent_messages[-1]["content"] == [{"type": "text", "text": "describe my assistant"}]
+
+
 def test_reasoning_model_with_reasoning_effort(mock_openai_client):
     """Test that reasoning_effort is passed to the API for Azure reasoning models."""
     config = AzureOpenAIConfig(model="o3-mini", reasoning_effort="low")

tests/llms/test_azure_openai_structured.py

@@ -264,3 +264,61 @@ def test_regular_model_sends_sampling_params(mock_azure_openai):
     assert "max_tokens" in call_kwargs  # standard sampling params still forwarded
     assert "top_p" in call_kwargs
     assert call_kwargs["model"] == "gpt-4o"
+
+
+@mock.patch("mem0.llms.azure_openai_structured.AzureOpenAI")
+def test_generate_response_does_not_mutate_caller_messages(mock_azure_openai):
+    mock_client = Mock()
+    mock_azure_openai.return_value = mock_client
+
+    config = DummyConfig(model="test-model", azure_kwargs=DummyAzureKwargs(api_key="real-key"))
+    llm = AzureOpenAIStructuredLLM(config)
+
+    mock_response = Mock()
+    mock_response.choices = [Mock(message=Mock(content="ok"))]
+    mock_client.chat.completions.create.return_value = mock_response
+
+    messages = [{"role": "user", "content": "my assistant helps me schedule meetings"}]
+    llm.generate_response(messages)
+
+    assert messages[-1]["content"] == "my assistant helps me schedule meetings"
+
+
+@mock.patch("mem0.llms.azure_openai_structured.AzureOpenAI")
+def test_generate_response_rewrites_assistant_keyword_for_model_only(mock_azure_openai):
+    mock_client = Mock()
+    mock_azure_openai.return_value = mock_client
+
+    config = DummyConfig(model="test-model", azure_kwargs=DummyAzureKwargs(api_key="real-key"))
+    llm = AzureOpenAIStructuredLLM(config)
+
+    mock_response = Mock()
+    mock_response.choices = [Mock(message=Mock(content="ok"))]
+    mock_client.chat.completions.create.return_value = mock_response
+
+    messages = [{"role": "user", "content": "my assistant helps me"}]
+    llm.generate_response(messages)
+
+    sent_messages = mock_client.chat.completions.create.call_args[1]["messages"]
+    assert sent_messages[-1]["content"] == "my ai helps me"
+    assert messages[-1]["content"] == "my assistant helps me"
+
+
+@mock.patch("mem0.llms.azure_openai_structured.AzureOpenAI")
+def test_generate_response_handles_multimodal_content(mock_azure_openai):
+    mock_client = Mock()
+    mock_azure_openai.return_value = mock_client
+
+    config = DummyConfig(model="test-model", azure_kwargs=DummyAzureKwargs(api_key="real-key"))
+    llm = AzureOpenAIStructuredLLM(config)
+
+    mock_response = Mock()
+    mock_response.choices = [Mock(message=Mock(content="ok"))]
+    mock_client.chat.completions.create.return_value = mock_response
+
+    messages = [{"role": "user", "content": [{"type": "text", "text": "describe my assistant"}]}]
+    response = llm.generate_response(messages)
+
+    assert response == "ok"
+    sent_messages = mock_client.chat.completions.create.call_args[1]["messages"]
+    assert sent_messages[-1]["content"] == [{"type": "text", "text": "describe my assistant"}]