Add architecture guard for direct str/int type identity checks

Co-authored-by: Shri Sukhani <shrisukhani@users.noreply.github.com>

Author: cursoragent

CONTRIBUTING.md

@@ -88,6 +88,7 @@ This runs lint, format checks, compile checks, tests, and package build.
   - `tests/test_architecture_marker_usage.py` (architecture marker coverage across guard modules),
   - `tests/test_readme_examples_listing.py` (README example-listing consistency enforcement),
   - `tests/test_plain_type_guard_usage.py` (`str`/`int` guardrail enforcement via plain-type checks),
+  - `tests/test_plain_type_identity_usage.py` (direct `type(... ) is str|int` guardrail enforcement via shared helpers),
   - `tests/test_type_utils_usage.py` (type `__mro__` boundary centralization in `hyperbrowser/type_utils.py`),
   - `tests/test_polling_loop_usage.py` (`while True` polling-loop centralization in `hyperbrowser/client/polling.py`),
   - `tests/test_core_type_helper_usage.py` (core transport/config/header/file/polling/session/error/parsing manager+tool module enforcement of shared plain-type helper usage),

tests/test_architecture_marker_usage.py

@@ -17,6 +17,7 @@
     "tests/test_pyproject_architecture_marker.py",
     "tests/test_architecture_marker_usage.py",
     "tests/test_plain_type_guard_usage.py",
+    "tests/test_plain_type_identity_usage.py",
     "tests/test_type_utils_usage.py",
     "tests/test_polling_loop_usage.py",
     "tests/test_core_type_helper_usage.py",

tests/test_plain_type_identity_usage.py

@@ -0,0 +1,22 @@
+import re
+from pathlib import Path
+
+import pytest
+
+pytestmark = pytest.mark.architecture
+
+
+_PLAIN_TYPE_IDENTITY_PATTERN = re.compile(
+    r"type\s*\([^)]*\)\s+is(?:\s+not)?\s+(?:str|int)\b"
+)
+
+
+def test_sdk_modules_avoid_direct_str_int_type_identity_checks():
+    violations: list[str] = []
+    for module_path in sorted(Path("hyperbrowser").rglob("*.py")):
+        module_text = module_path.read_text(encoding="utf-8")
+        for line_number, line_text in enumerate(module_text.splitlines(), start=1):
+            if _PLAIN_TYPE_IDENTITY_PATTERN.search(line_text):
+                violations.append(f"{module_path}:{line_number}")
+
+    assert violations == []