diff --git a/tests/client/test_errors.py b/tests/client/test_errors.py
new file mode 100644
index 00000000..30c4468d
--- /dev/null
+++ b/tests/client/test_errors.py
@@ -0,0 +1,201 @@
+import pytest
+
+from a2a.client import A2AClientError, A2AClientHTTPError, A2AClientJSONError
+
+
+class TestA2AClientError:
+    """Test cases for the base A2AClientError class."""
+
+    def test_instantiation(self):
+        """Test that A2AClientError can be instantiated."""
+        error = A2AClientError('Test error message')
+        assert isinstance(error, Exception)
+        assert str(error) == 'Test error message'
+
+    def test_inheritance(self):
+        """Test that A2AClientError inherits from Exception."""
+        error = A2AClientError()
+        assert isinstance(error, Exception)
+
+
+class TestA2AClientHTTPError:
+    """Test cases for A2AClientHTTPError class."""
+
+    def test_instantiation(self):
+        """Test that A2AClientHTTPError can be instantiated with status_code and message."""
+        error = A2AClientHTTPError(404, 'Not Found')
+        assert isinstance(error, A2AClientError)
+        assert error.status_code == 404
+        assert error.message == 'Not Found'
+
+    def test_message_formatting(self):
+        """Test that the error message is formatted correctly."""
+        error = A2AClientHTTPError(500, 'Internal Server Error')
+        assert str(error) == 'HTTP Error 500: Internal Server Error'
+
+    def test_inheritance(self):
+        """Test that A2AClientHTTPError inherits from A2AClientError."""
+        error = A2AClientHTTPError(400, 'Bad Request')
+        assert isinstance(error, A2AClientError)
+
+    def test_with_empty_message(self):
+        """Test behavior with an empty message."""
+        error = A2AClientHTTPError(403, '')
+        assert error.status_code == 403
+        assert error.message == ''
+        assert str(error) == 'HTTP Error 403: '
+
+    def test_with_various_status_codes(self):
+        """Test with different HTTP status codes."""
+        test_cases = [
+            (200, 'OK'),
+            (201, 'Created'),
+            (400, 'Bad Request'),
+            (401, 'Unauthorized'),
+            (403, 'Forbidden'),
+            (404, 'Not Found'),
+            (500, 'Internal Server Error'),
+            (503, 'Service Unavailable'),
+        ]
+
+        for status_code, message in test_cases:
+            error = A2AClientHTTPError(status_code, message)
+            assert error.status_code == status_code
+            assert error.message == message
+            assert str(error) == f'HTTP Error {status_code}: {message}'
+
+
+class TestA2AClientJSONError:
+    """Test cases for A2AClientJSONError class."""
+
+    def test_instantiation(self):
+        """Test that A2AClientJSONError can be instantiated with a message."""
+        error = A2AClientJSONError('Invalid JSON format')
+        assert isinstance(error, A2AClientError)
+        assert error.message == 'Invalid JSON format'
+
+    def test_message_formatting(self):
+        """Test that the error message is formatted correctly."""
+        error = A2AClientJSONError('Missing required field')
+        assert str(error) == 'JSON Error: Missing required field'
+
+    def test_inheritance(self):
+        """Test that A2AClientJSONError inherits from A2AClientError."""
+        error = A2AClientJSONError('Parsing error')
+        assert isinstance(error, A2AClientError)
+
+    def test_with_empty_message(self):
+        """Test behavior with an empty message."""
+        error = A2AClientJSONError('')
+        assert error.message == ''
+        assert str(error) == 'JSON Error: '
+
+    def test_with_various_messages(self):
+        """Test with different error messages."""
+        test_messages = [
+            'Malformed JSON',
+            'Missing required fields',
+            'Invalid data type',
+            'Unexpected JSON structure',
+            'Empty JSON object',
+        ]
+
+        for message in test_messages:
+            error = A2AClientJSONError(message)
+            assert error.message == message
+            assert str(error) == f'JSON Error: {message}'
+
+
+class TestExceptionHierarchy:
+    """Test the exception hierarchy and relationships."""
+
+    def test_exception_hierarchy(self):
+        """Test that the exception hierarchy is correct."""
+        assert issubclass(A2AClientError, Exception)
+        assert issubclass(A2AClientHTTPError, A2AClientError)
+        assert issubclass(A2AClientJSONError, A2AClientError)
+
+    def test_catch_specific_exception(self):
+        """Test that specific exceptions can be caught."""
+        try:
+            raise A2AClientHTTPError(404, 'Not Found')
+        except A2AClientHTTPError as e:
+            assert e.status_code == 404
+            assert e.message == 'Not Found'
+
+    def test_catch_base_exception(self):
+        """Test that derived exceptions can be caught as base exception."""
+        exceptions = [
+            A2AClientHTTPError(404, 'Not Found'),
+            A2AClientJSONError('Invalid JSON'),
+        ]
+
+        for raised_error in exceptions:
+            try:
+                raise raised_error
+            except A2AClientError as e:
+                assert isinstance(e, A2AClientError)
+
+
+class TestExceptionRaising:
+    """Test cases for raising and handling the exceptions."""
+
+    def test_raising_http_error(self):
+        """Test raising an HTTP error and checking its properties."""
+        with pytest.raises(A2AClientHTTPError) as excinfo:
+            raise A2AClientHTTPError(429, 'Too Many Requests')
+
+        error = excinfo.value
+        assert error.status_code == 429
+        assert error.message == 'Too Many Requests'
+        assert str(error) == 'HTTP Error 429: Too Many Requests'
+
+    def test_raising_json_error(self):
+        """Test raising a JSON error and checking its properties."""
+        with pytest.raises(A2AClientJSONError) as excinfo:
+            raise A2AClientJSONError('Invalid format')
+
+        error = excinfo.value
+        assert error.message == 'Invalid format'
+        assert str(error) == 'JSON Error: Invalid format'
+
+    def test_raising_base_error(self):
+        """Test raising the base error."""
+        with pytest.raises(A2AClientError) as excinfo:
+            raise A2AClientError('Generic client error')
+
+        assert str(excinfo.value) == 'Generic client error'
+
+
+# Additional parametrized tests for more comprehensive coverage
+
+
+@pytest.mark.parametrize(
+    'status_code,message,expected',
+    [
+        (400, 'Bad Request', 'HTTP Error 400: Bad Request'),
+        (404, 'Not Found', 'HTTP Error 404: Not Found'),
+        (500, 'Server Error', 'HTTP Error 500: Server Error'),
+    ],
+)
+def test_http_error_parametrized(status_code, message, expected):
+    """Parametrized test for HTTP errors with different status codes."""
+    error = A2AClientHTTPError(status_code, message)
+    assert error.status_code == status_code
+    assert error.message == message
+    assert str(error) == expected
+
+
+@pytest.mark.parametrize(
+    'message,expected',
+    [
+        ('Missing field', 'JSON Error: Missing field'),
+        ('Invalid type', 'JSON Error: Invalid type'),
+        ('Parsing failed', 'JSON Error: Parsing failed'),
+    ],
+)
+def test_json_error_parametrized(message, expected):
+    """Parametrized test for JSON errors with different messages."""
+    error = A2AClientJSONError(message)
+    assert error.message == message
+    assert str(error) == expected