fix: Address mypy failures in google_api_tool/

Co-authored-by: Xuan Yang <xygoogle@google.com>
PiperOrigin-RevId: 943533056

Author: xuanyang15

pyproject.toml

@@ -306,6 +306,9 @@ python_version = "3.11"
 disable_error_code = [ "import-not-found", "import-untyped", "unused-ignore" ]
 strict = true
 plugins = [ "pydantic.mypy" ]
+overrides = [ { module = [
+  "google.auth.*",
+], ignore_missing_imports = true, follow_imports = "skip" } ]
 
 [tool.pytest]
 ini_options.testpaths = [ "tests" ]

src/google/adk/tools/google_api_tool/google_api_toolset.py

@@ -90,8 +90,12 @@ def __init__(
       cert_path, key_path, passphrase = self._mtls_certs.get_certs()
       if cert_path and key_path and passphrase:
 
-        def client_factory():
-          return httpx.AsyncClient(cert=(cert_path, key_path, passphrase))
+        def client_factory() -> httpx.AsyncClient:
+          if passphrase:
+            return httpx.AsyncClient(
+                cert=(cert_path, key_path, passphrase)  # type: ignore[arg-type]
+            )
+          return httpx.AsyncClient(cert=(cert_path, key_path))
 
         self._httpx_client_factory = client_factory
 

src/google/adk/tools/google_api_tool/googleapi_to_openapi_converter.py

@@ -130,6 +130,9 @@ def convert(self) -> Dict[str, Any]:
     if not self._google_api_spec:
       self.fetch_google_api_spec()
 
+    if self._google_api_spec is None:
+      raise RuntimeError("Failed to initialize Google API specification.")
+
     # Convert basic API information
     self._convert_info()
 
@@ -170,6 +173,8 @@ def _convert_info(self) -> None:
 
   def _convert_servers(self) -> None:
     """Convert server information."""
+    if self._google_api_spec is None:
+      raise RuntimeError("API spec must be initialized before conversion.")
     use_client_cert = getattr(self, "_use_client_cert", False)
     if use_client_cert and "mtlsRootUrl" in self._google_api_spec:
       root_url = self._google_api_spec["mtlsRootUrl"]