diff --git a/webdriver/tests/bidi/network/add_intercept/__init__.py b/webdriver/tests/bidi/network/add_intercept/__init__.py
new file mode 100644
index 00000000000000..e69de29bb2d1d6
diff --git a/webdriver/tests/bidi/network/add_intercept/invalid.py b/webdriver/tests/bidi/network/add_intercept/invalid.py
new file mode 100644
index 00000000000000..dc15d5ea904e29
--- /dev/null
+++ b/webdriver/tests/bidi/network/add_intercept/invalid.py
@@ -0,0 +1,171 @@
+import pytest
+import webdriver.bidi.error as error
+
+pytestmark = pytest.mark.asyncio
+
+
+@pytest.mark.parametrize("value", [None, "foo", False, 42, {}])
+async def test_params_phases_invalid_type(bidi_session, value):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(phases=value)
+
+
+async def test_params_phases_invalid_value_empty_array(bidi_session):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(phases=[])
+
+
+@pytest.mark.parametrize("value", [None, False, 42, {}, []])
+async def test_params_phases_entry_invalid_type(bidi_session, value):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(phases=[value])
+
+
+@pytest.mark.parametrize("value", ["foo", "responseCompleted"])
+async def test_params_phases_entry_invalid_value(bidi_session, value):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(phases=[value])
+
+
+@pytest.mark.parametrize("value", ["foo", False, 42, {}])
+async def test_params_url_patterns_invalid_type(bidi_session, value):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(
+            phases=["beforeRequestSent"], url_patterns=value
+        )
+
+
+@pytest.mark.parametrize("value", [None, "foo", False, 42, []])
+async def test_params_url_patterns_entry_invalid_type(bidi_session, value):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(
+            phases=["beforeRequestSent"], url_patterns=[value]
+        )
+
+
+@pytest.mark.parametrize("value", [{}, {"type": "foo"}])
+async def test_params_url_patterns_entry_invalid_value(bidi_session, value):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(
+            phases=["beforeRequestSent"], url_patterns=[value]
+        )
+
+
+@pytest.mark.parametrize("value", [None, False, 42, [], {}])
+async def test_params_url_patterns_string_pattern_invalid_type(bidi_session, value):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(
+            phases=["beforeRequestSent"],
+            url_patterns=[{"type": "string", "pattern": value}],
+        )
+
+
+@pytest.mark.parametrize(
+    "value",
+    [
+        "foo",
+        "*",
+        "(",
+        ")",
+        "{",
+        "}",
+        "http\\{s\\}://example.com",
+        "https://example.com:port/",
+    ],
+)
+async def test_params_url_patterns_string_pattern_invalid_value(bidi_session, value):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(
+            phases=["beforeRequestSent"],
+            url_patterns=[{"type": "string", "pattern": value}],
+        )
+
+
+@pytest.mark.parametrize(
+    "property", ["protocol", "hostname", "port", "pathname", "search"]
+)
+@pytest.mark.parametrize("value", [False, 42, [], {}])
+async def test_params_url_patterns_pattern_property_invalid_type(
+    bidi_session, property, value
+):
+    with pytest.raises(error.InvalidArgumentException):
+        url_pattern = {"type": "pattern"}
+        url_pattern[property] = value
+        await bidi_session.network.add_intercept(
+            phases=["beforeRequestSent"],
+            url_patterns=[url_pattern],
+        )
+
+
+@pytest.mark.parametrize(
+    "property", ["protocol", "hostname", "port", "pathname", "search"]
+)
+@pytest.mark.parametrize("value", ["*", "(", ")", "{", "}"])
+async def test_params_url_patterns_pattern_property_unescaped_character(
+    bidi_session, property, value
+):
+    with pytest.raises(error.InvalidArgumentException):
+        url_pattern = {"type": "pattern"}
+        url_pattern[property] = value
+        await bidi_session.network.add_intercept(
+            phases=["beforeRequestSent"],
+            url_patterns=[url_pattern],
+        )
+
+
+@pytest.mark.parametrize(
+    "value",
+    [
+        "http/",
+        "http\\*",
+        "http\\(",
+        "http\\)",
+        "http\\{",
+        "http\\}",
+        "http#",
+        "http@",
+        "http%",
+    ],
+)
+async def test_params_url_patterns_pattern_protocol_invalid_value(bidi_session, value):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(
+            phases=["beforeRequestSent"],
+            url_patterns=[{"type": "pattern", "protocol": value}],
+        )
+
+
+@pytest.mark.parametrize("value", ["abc/com/", "abc?com", "abc#com", "abc:com", "::1"])
+async def test_params_url_patterns_pattern_hostname_invalid_value(bidi_session, value):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(
+            phases=["beforeRequestSent"],
+            url_patterns=[{"type": "pattern", "hostname": value}],
+        )
+
+
+@pytest.mark.parametrize("value", ["abcd", "-1", "80 ", "1.3", ":80", "65536"])
+async def test_params_url_patterns_pattern_port_invalid_value(bidi_session, value):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(
+            phases=["beforeRequestSent"],
+            url_patterns=[{"type": "pattern", "port": value}],
+        )
+
+
+@pytest.mark.parametrize("value", ["path?", "path#"])
+async def test_params_url_patterns_pattern_pathname_invalid_value(bidi_session, value):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(
+            phases=["beforeRequestSent"],
+            url_patterns=[{"type": "pattern", "pathname": value}],
+        )
+
+
+@pytest.mark.parametrize("value", ["search#"])
+async def test_params_url_patterns_pattern_search_invalid_value(bidi_session, value):
+    with pytest.raises(error.InvalidArgumentException):
+        await bidi_session.network.add_intercept(
+            phases=["beforeRequestSent"],
+            url_patterns=[{"type": "pattern", "search": value}],
+        )