diff --git a/tests/test_cmd.py b/tests/test_cmd.py
new file mode 100644
index 0000000..2e615da
--- /dev/null
+++ b/tests/test_cmd.py
@@ -0,0 +1,86 @@
+import sys
+import tempfile
+from io import StringIO
+from unittest.mock import MagicMock
+
+from modelz.client import ModelzClient, ModelzResponse
+from modelz.cmd import console, inference
+from modelz.serde import RawSerde
+
+
+def test_inference(monkeypatch):
+    # Mocking the behavior of `ModelzClient.inference`
+    params_dict = {"key": "value"}
+    params_as_saved_in_file = b"Mocked Response" + b" saved in file"
+    # output_file = "output.bin"
+    # use a temp file instead
+    output_file = tempfile.NamedTemporaryFile().name
+    output_written_message = f"result has been written in {output_file}\n"
+
+    try:
+
+        def mock_inference(self, params, serde):
+            mock_response = ModelzResponse(
+                resp=MagicMock(status_code=200, content=params),
+                serde=RawSerde(),
+            )
+            return mock_response
+
+        # Patching the `client.inference` method with the mock
+        monkeypatch.setattr(ModelzClient, "inference", mock_inference)
+        mock_init = MagicMock()
+        mock_init.return_value = None
+        monkeypatch.setattr(ModelzClient, "__init__", mock_init)
+
+        # Creating a StringIO object to capture the console output
+        console_output = StringIO()
+        console.file = console_output
+
+        # Running the inference function with the mocked client and write to file
+        inference(
+            deployment="deployment_id",
+            params=params_dict,
+            read_stdin=False,
+        )
+
+        # Asserting the console output
+        expected_output = "{'key': 'value'}\n"
+        assert console_output.getvalue() == expected_output
+
+        # sys.stdin = StringIO(stdin_input)
+        # Mocking the behavior of `sys.stdin.buffer.read()`
+        mock_stdin_read = MagicMock(return_value=params_as_saved_in_file)
+
+        # Patching the `sys.stdin.buffer.read()` with the mock
+        monkeypatch.setattr(sys.stdin.buffer, "read", mock_stdin_read)
+
+        console_output = StringIO()
+        console.file = console_output
+
+        inference(
+            deployment="deployment_id",
+            read_stdin=True,
+            write_file=output_file,
+        )
+
+        # Asserting the file content
+        with open(output_file, "rb") as file:
+            file_content = file.read()
+            assert file_content == params_as_saved_in_file
+
+        # Asserting the console output
+        assert console_output.getvalue() == output_written_message
+
+    except Exception as e:
+        raise e
+
+    finally:
+        # Resetting the sys.stdin
+        # sys.stdin = sys.__stdin__
+        monkeypatch.undo()
+
+        # remove output_file if exists
+        import os
+
+        if os.path.exists(output_file):
+            os.remove(output_file)
diff --git a/tests/test_env.py b/tests/test_env.py
new file mode 100644
index 0000000..17c1e4c
--- /dev/null
+++ b/tests/test_env.py
@@ -0,0 +1,26 @@
+import os
+
+import pytest
+
+from modelz.env import EnvConfig
+
+
+@pytest.fixture
+def config():
+    os.environ["MODELZ_API_KEY"] = "abc123"
+    os.environ["MODELZ_HOST"] = "https://custom.host/"
+    yield EnvConfig()
+    os.environ.pop("MODELZ_API_KEY")
+    os.environ.pop("MODELZ_HOST")
+
+
+def test_update_from_env(config):
+    assert config.api_key == "abc123"
+    assert config.host == "https://custom.host/"
+
+
+def test_default():
+    with pytest.raises(AttributeError):
+        config = EnvConfig()
+        assert config.api_key is None
+        assert config.host == "https://{}.modelz.io/"