diff --git a/backend/app/api/routes/responses.py b/backend/app/api/routes/responses.py
index fc10cd479..ed098af6f 100644
--- a/backend/app/api/routes/responses.py
+++ b/backend/app/api/routes/responses.py
@@ -106,21 +106,27 @@ def process_response(
         f"Starting generating response for assistant_id={request.assistant_id}, project_id={request.project_id}, organization_id={organization_id}"
     )
     try:
-        response = client.responses.create(
-            model=assistant.model,
-            previous_response_id=request.response_id,
-            instructions=assistant.instructions,
-            tools=[
+        # Create response with or without tools based on vector_store_id
+        params = {
+            "model": assistant.model,
+            "previous_response_id": request.response_id,
+            "instructions": assistant.instructions,
+            "temperature": assistant.temperature,
+            "input": [{"role": "user", "content": request.question}],
+        }
+
+        if assistant.vector_store_id:
+            params["tools"] = [
                 {
                     "type": "file_search",
                     "vector_store_ids": [assistant.vector_store_id],
                     "max_num_results": assistant.max_num_results,
                 }
-            ],
-            temperature=assistant.temperature,
-            input=[{"role": "user", "content": request.question}],
-            include=["file_search_call.results"],
-        )
+            ]
+            params["include"] = ["file_search_call.results"]
+
+        response = client.responses.create(**params)
+
         response_chunks = get_file_search_results(response)
         logger.info(
             f"Successfully generated response: response_id={response.id}, assistant={request.assistant_id}, project_id={request.project_id}, organization_id={organization_id}"
diff --git a/backend/app/tests/api/routes/test_responses.py b/backend/app/tests/api/routes/test_responses.py
index 40de2d81b..257d2585a 100644
--- a/backend/app/tests/api/routes/test_responses.py
+++ b/backend/app/tests/api/routes/test_responses.py
@@ -70,3 +70,72 @@ def test_responses_endpoint_success(
     assert response_json["success"] is True
     assert response_json["data"]["status"] == "processing"
     assert response_json["data"]["message"] == "Response creation started"
+
+
+@patch("app.api.routes.responses.OpenAI")
+@patch("app.api.routes.responses.get_provider_credential")
+@patch("app.api.routes.responses.get_assistant_by_id")
+def test_responses_endpoint_without_vector_store(
+    mock_get_assistant,
+    mock_get_credential,
+    mock_openai,
+    db,
+):
+    """Test the /responses endpoint when assistant has no vector store configured."""
+    # Setup mock credentials
+    mock_get_credential.return_value = {"api_key": "test_api_key"}
+
+    # Setup mock assistant without vector store
+    mock_assistant = MagicMock()
+    mock_assistant.model = "gpt-4"
+    mock_assistant.instructions = "Test instructions"
+    mock_assistant.temperature = 0.1
+    mock_assistant.vector_store_id = None  # No vector store configured
+    mock_get_assistant.return_value = mock_assistant
+
+    # Setup mock OpenAI client
+    mock_client = MagicMock()
+    mock_openai.return_value = mock_client
+
+    # Setup the mock response object
+    mock_response = MagicMock()
+    mock_response.id = "mock_response_id"
+    mock_response.output_text = "Test output"
+    mock_response.model = "gpt-4"
+    mock_response.usage.input_tokens = 10
+    mock_response.usage.output_tokens = 5
+    mock_response.usage.total_tokens = 15
+    # No output attribute since there are no tool calls
+    mock_client.responses.create.return_value = mock_response
+
+    # Get the Glific project ID
+    glific_project = db.exec(select(Project).where(Project.name == "Glific")).first()
+    if not glific_project:
+        pytest.skip("Glific project not found in the database")
+
+    # Use the original API key from seed data
+    original_api_key = "ApiKey No3x47A5qoIGhm0kVKjQ77dhCqEdWRIQZlEPzzzh7i8"
+
+    headers = {"X-API-KEY": original_api_key}
+    request_data = {
+        "project_id": glific_project.id,
+        "assistant_id": "assistant_123",
+        "question": "What is Glific?",
+        "callback_url": "http://example.com/callback",
+    }
+
+    response = client.post("/responses", json=request_data, headers=headers)
+    assert response.status_code == 200
+    response_json = response.json()
+    assert response_json["success"] is True
+    assert response_json["data"]["status"] == "processing"
+    assert response_json["data"]["message"] == "Response creation started"
+
+    # Verify OpenAI client was called without tools
+    mock_client.responses.create.assert_called_once_with(
+        model=mock_assistant.model,
+        previous_response_id=None,
+        instructions=mock_assistant.instructions,
+        temperature=mock_assistant.temperature,
+        input=[{"role": "user", "content": "What is Glific?"}],
+    )