diff --git a/README.md b/README.md
index db58441..de9896e 100644
--- a/README.md
+++ b/README.md
@@ -51,7 +51,7 @@ https://github.com/fujitatomoya/ros2ai/assets/43395114/2af4fd44-2ccf-472c-9153-c
 - `rolling` / `jazzy`
 
   ```bash
-  pip install openai ollama --break-system-packages
+  pip install openai ollama validators --break-system-packages
   ```
 
   > [!NOTE]
@@ -60,7 +60,7 @@ https://github.com/fujitatomoya/ros2ai/assets/43395114/2af4fd44-2ccf-472c-9153-c
 - `iron` / `humble`
 
   ```bash
-  pip install openai ollama
+  pip install openai ollama validators
   ```
 
 ### Build
diff --git a/docker/Dockerfile b/docker/Dockerfile
index e60274c..e2bc418 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -39,11 +39,11 @@ RUN apt-get update \
 
 # Adapt pip install option based on distro (technically ubuntu version)
 RUN if [ "$ROS_DISTRO" = "humble" ]; then \
-        pip install openai ollama; \
+        pip install openai ollama validators; \
     elif [ "$ROS_DISTRO" = "iron" ]; then \
-        pip install openai ollama; \
+        pip install openai ollama validators; \
     else \
-        pip install openai ollama --break-system-packages; \
+        pip install openai ollama validators --break-system-packages; \
     fi
 
 # Build and source colcon workspace
diff --git a/package.xml b/package.xml
index 16c54ca..fe40ae9 100644
--- a/package.xml
+++ b/package.xml
@@ -15,6 +15,8 @@
 
   <exec_depend>curl</exec_depend>
   <exec_depend>python3-openai-pip</exec_depend>
+  <exec_depend>python3-ollama-pip</exec_depend>
+  <exec_depend>python3-validotors-pip</exec_depend>
   <exec_depend>ros2cli</exec_depend>
 
   <test_depend>ament_copyright</test_depend>
diff --git a/ros2ai/api/config.py b/ros2ai/api/config.py
index 55e5e11..cfc9e61 100644
--- a/ros2ai/api/config.py
+++ b/ros2ai/api/config.py
@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import validators
 import os
 
 import ros2ai.api.constants as constants
@@ -36,7 +37,6 @@ def get_ai_model() -> str:
     """
     model_name = os.environ.get(constants.ROS_OPENAI_MODEL_NAME_ENV_VAR)
     if not model_name:
-        print('AI model is not set, defaults to ' + constants.ROS_OPENAI_DEFAULT_MODEL)
         return constants.ROS_OPENAI_DEFAULT_MODEL
     else:
         return model_name
@@ -48,12 +48,16 @@ def get_endpoint_url() -> str:
     :return: string of OpenAI API service endpoint URL, could be None.
     """
     url = os.environ.get(constants.ROS_OPENAI_ENDPOINT_ENV_VAR)
-    # TODO(@fujitatomoya):check if that is valid url before return.
-    if not url:
-        print('AI model is not set, defaults to ' + constants.ROS_OPENAI_DEFAULT_ENDPOINT)
+    url_valid = False
+    try:
+        url_valid = validators.url(url)
+    except Exception as e:
+        print(f"Error validating URL: {e}")
         return constants.ROS_OPENAI_DEFAULT_ENDPOINT
-    else:
+    if url and url_valid:
         return url
+    else:
+        return constants.ROS_OPENAI_DEFAULT_ENDPOINT
 
 def get_temperature() -> float:
     """
diff --git a/scripts/github_workflows.sh b/scripts/github_workflows.sh
index a732c55..3486f2d 100755
--- a/scripts/github_workflows.sh
+++ b/scripts/github_workflows.sh
@@ -41,9 +41,9 @@ function install_prerequisites () {
     # TODO@fujitatomoya: should install openai via package.xml
     apt install -y pip
     if [ $UBUNTU_VERSION == "24.04" ]; then
-        pip install openai ollama --break-system-packages
+        pip install openai ollama validators --break-system-packages
     else
-        pip install openai ollama
+        pip install openai ollama validators
     fi
     #apt install -y ros-${ROS_DISTRO}-desktop --no-install-recommends
     cd $there