feat: migrate Agent Engines, Evaluation, Prompt Management, and Skill features to agentplatform

PiperOrigin-RevId: 914975401

Author: yyyu-google

agentplatform/__init__.py

@@ -15,13 +15,20 @@
 """The agentplatform module."""
 
 import importlib
+import sys
+
 from google.cloud.aiplatform import init
 from google.cloud.aiplatform import version as aiplatform_version
 
 __version__ = aiplatform_version.__version__
 
+_genai_client = None
+_genai_types = None
+
 
 def __getattr__(name):  # type: ignore[no-untyped-def]
+    # Lazy importing the preview submodule
+    # See https://peps.python.org/pep-0562/
     if name == "preview":
         # We need to import carefully to avoid `RecursionError`.
         # This won't work since it causes `RecursionError`:
@@ -30,10 +37,26 @@ def __getattr__(name):  # type: ignore[no-untyped-def]
         # `import google.cloud.aiplatform.agentplatform.preview as`
         #    `agentplatform_preview`
         return importlib.import_module(".preview", __name__)
+    if name == "Client":
+        global _genai_client
+        if _genai_client is None:
+            _genai_client = importlib.import_module("._genai.client", __name__)
+        return getattr(_genai_client, name)
+
+    if name == "types":
+        global _genai_types
+        if _genai_types is None:
+            _genai_types = importlib.import_module("._genai.types", __name__)
+        if "vertexai.types" not in sys.modules:
+            sys.modules["vertexai.types"] = _genai_types
+        return _genai_types
+
     raise AttributeError(f"module '{__name__}' has no attribute '{name}'")
 
 
 __all__ = [
     "init",
     "preview",
+    "Client",
+    "types",
 ]

agentplatform/_genai/__init__.py

@@ -0,0 +1,43 @@
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+"""The agentplatform module."""
+
+import importlib
+
+from .client import Client
+
+_evals = None
+
+
+def __getattr__(name):  # type: ignore[no-untyped-def]
+    if name == "evals":
+        global _evals
+        if _evals is None:
+            try:
+                _evals = importlib.import_module(".evals", __package__)
+            except ImportError as e:
+                raise ImportError(
+                    "The 'evals' module requires additional dependencies. "
+                    "Please install them using pip install "
+                    "google-cloud-aiplatform[evaluation]"
+                ) from e
+        return _evals
+    raise AttributeError(f"module '{__name__}' has no attribute '{name}'")
+
+
+__all__ = [
+    "Client",
+    "evals",
+]