feat(config): add --type flag to adk create to allow starting with config

Updated the `adk create` default model version to gemini-2.5-flash.

PiperOrigin-RevId: 788589859

src/google/adk/cli/cli_create.py

@@ -14,6 +14,7 @@
 
 from __future__ import annotations
 
+import enum
 import os
 import subprocess
 from typing import Optional
@@ -21,6 +22,12 @@ from typing import Tuple
 
 import click
 
+
+class Type(enum.Enum):
+  CONFIG = "config"
+  CODE = "code"
+
+
 _INIT_PY_TEMPLATE = """\
 from . import agent
 """
@@ -36,6 +43,13 @@ root_agent = Agent(
 )
 """
 
+_AGENT_CONFIG_TEMPLATE = """\
+name: root_agent
+description: A helpful assistant for user questions.
+instruction: Answer user questions to the best of your knowledge
+model: {model_name}
+"""
+
 
 _GOOGLE_API_MSG = """
 Don't have API Key? Create one in AI Studio: https://aistudio.google.com/apikey
@@ -51,13 +65,20 @@ Please see below guide to configure other models:
 https://google.github.io/adk-docs/agents/models
 """
 
-_SUCCESS_MSG = """
+_SUCCESS_MSG_CODE = """
 Agent created in {agent_folder}:
 - .env
 - __init__.py
 - agent.py
 """
 
+_SUCCESS_MSG_CONFIG = """
+Agent created in {agent_folder}:
+- .env
+- __init__.py
+- root_agent.yaml
+"""
+
 
 def _get_gcp_project_from_gcloud() -> str:
   """Uses gcloud to get default project."""
@@ -158,13 +179,15 @@ def _generate_files(
     google_cloud_project: Optional[str] = None,
     google_cloud_region: Optional[str] = None,
     model: Optional[str] = None,
+    type: Optional[Type] = None,
 ):
   """Generates a folder name for the agent."""
   os.makedirs(agent_folder, exist_ok=True)
 
   dotenv_file_path = os.path.join(agent_folder, ".env")
   init_file_path = os.path.join(agent_folder, "__init__.py")
-  agent_file_path = os.path.join(agent_folder, "agent.py")
+  agent_py_file_path = os.path.join(agent_folder, "agent.py")
+  agent_config_file_path = os.path.join(agent_folder, "root_agent.yaml")
 
   with open(dotenv_file_path, "w", encoding="utf-8") as f:
     lines = []
@@ -180,29 +203,38 @@ def _generate_files(
       lines.append(f"GOOGLE_CLOUD_LOCATION={google_cloud_region}")
     f.write("\n".join(lines))
 
-  with open(init_file_path, "w", encoding="utf-8") as f:
-    f.write(_INIT_PY_TEMPLATE)
+  if type == Type.CONFIG:
+    with open(agent_config_file_path, "w", encoding="utf-8") as f:
+      f.write(_AGENT_CONFIG_TEMPLATE.format(model_name=model))
+    with open(init_file_path, "w", encoding="utf-8") as f:
+      f.write("")
+    click.secho(
+        _SUCCESS_MSG_CONFIG.format(agent_folder=agent_folder),
+        fg="green",
+    )
+  else:
+    with open(init_file_path, "w", encoding="utf-8") as f:
+      f.write(_INIT_PY_TEMPLATE)
 
-  with open(agent_file_path, "w", encoding="utf-8") as f:
-    f.write(_AGENT_PY_TEMPLATE.format(model_name=model))
-
-  click.secho(
-      _SUCCESS_MSG.format(agent_folder=agent_folder),
-      fg="green",
-  )
+    with open(agent_py_file_path, "w", encoding="utf-8") as f:
+      f.write(_AGENT_PY_TEMPLATE.format(model_name=model))
+    click.secho(
+        _SUCCESS_MSG_CODE.format(agent_folder=agent_folder),
+        fg="green",
+    )
 
 
 def _prompt_for_model() -> str:
   model_choice = click.prompt(
       """\
 Choose a model for the root agent:
-1. gemini-2.0-flash-001
+1. gemini-2.5-flash
 2. Other models (fill later)
 Choose model""",
       type=click.Choice(["1", "2"]),
   )
   if model_choice == "1":
-    return "gemini-2.0-flash-001"
+    return "gemini-2.5-flash"
   else:
     click.secho(_OTHER_MODEL_MSG, fg="green")
     return "<FILL_IN_MODEL>"
@@ -231,6 +263,22 @@ def _prompt_to_choose_backend(
   return google_api_key, google_cloud_project, google_cloud_region
 
 
+def _prompt_to_choose_type() -> Type:
+  """Prompts user to choose type of agent to create."""
+  type_choice = click.prompt(
+      """\
+Choose a type for the root agent:
+1. YAML config (experimental, may change without notice)
+2. Code
+Choose type""",
+      type=click.Choice(["1", "2"]),
+  )
+  if type_choice == "1":
+    return Type.CONFIG
+  else:
+    return Type.CODE
+
+
 def run_cmd(
     agent_name: str,
     *,
@@ -238,6 +286,7 @@ def run_cmd(
     google_api_key: Optional[str],
     google_cloud_project: Optional[str],
     google_cloud_region: Optional[str],
+    type: Optional[Type],
 ):
   """Runs `adk create` command to create agent template.
 
@@ -249,6 +298,7 @@ def run_cmd(
       VertexAI as backend.
     google_cloud_region: Optional[str], The Google Cloud region for using
       VertexAI as backend.
+    type: Optional[Type], Whether to define agent with config file or code.
   """
   agent_folder = os.path.join(os.getcwd(), agent_name)
   # check folder doesn't exist or it's empty. Otherwise, throw
@@ -272,10 +322,14 @@ def run_cmd(
           )
       )
 
+  if not type:
+    type = _prompt_to_choose_type()
+
   _generate_files(
       agent_folder,
       google_api_key=google_api_key,
       google_cloud_project=google_cloud_project,
       google_cloud_region=google_cloud_region,
       model=model,
+      type=type,
   )

src/google/adk/cli/cli_tools_click.py

@@ -33,8 +33,6 @@ from . import cli_create
 from . import cli_deploy
 from .. import version
 from ..evaluation.constants import MISSING_EVAL_DEPENDENCIES_MESSAGE
-from ..evaluation.gcs_eval_set_results_manager import GcsEvalSetResultsManager
-from ..evaluation.gcs_eval_sets_manager import GcsEvalSetsManager
 from ..evaluation.local_eval_set_results_manager import LocalEvalSetResultsManager
 from ..sessions.in_memory_session_service import InMemorySessionService
 from .cli import run_cli
@@ -147,6 +145,18 @@ def deploy():
     type=str,
     help="Optional. The Google Cloud Region for using VertexAI as backend.",
 )
+@click.option(
+    "--type",
+    type=click.Choice([t.value for t in cli_create.Type]),
+    help=(
+        "EXPERIMENTAL Optional. Type of agent to create: 'config' or 'code'."
+        " 'config' is not ready for use so it defaults to 'code'. It may change"
+        " later once 'config' is ready for use."
+    ),
+    default=cli_create.Type.CODE.value,
+    show_default=True,
+    hidden=True,  # Won't show in --help output. Not ready for use.
+)
 @click.argument("app_name", type=str, required=True)
 def cli_create_cmd(
     app_name: str,
@@ -154,6 +164,7 @@ def cli_create_cmd(
     api_key: Optional[str],
     project: Optional[str],
     region: Optional[str],
+    type: Optional[cli_create.Type],
 ):
   """Creates a new app in the current folder with prepopulated agent template.
 
@@ -169,6 +180,7 @@ def cli_create_cmd(
       google_api_key=api_key,
       google_cloud_project=project,
       google_cloud_region=region,
+      type=type,
   )
 
 

tests/unittests/cli/utils/test_cli_create.py

@@ -147,9 +147,53 @@ def test_run_cmd_overwrite_reject(
         google_api_key=None,
         google_cloud_project=None,
         google_cloud_region=None,
+        type=cli_create.Type.CODE,
     )
 
 
+def test_run_cmd_with_type_config(
+    monkeypatch: pytest.MonkeyPatch, tmp_path: Path
+) -> None:
+  """run_cmd with --type=config should generate YAML config file."""
+  agent_name = "test_agent"
+
+  monkeypatch.setattr(os, "getcwd", lambda: str(tmp_path))
+  monkeypatch.setattr(os.path, "exists", lambda _p: False)
+
+  cli_create.run_cmd(
+      agent_name,
+      model="gemini-2.0-flash-001",
+      google_api_key="test-key",
+      google_cloud_project=None,
+      google_cloud_region=None,
+      type=cli_create.Type.CONFIG,
+  )
+
+  agent_dir = tmp_path / agent_name
+  assert agent_dir.exists()
+
+  # Should create root_agent.yaml instead of agent.py
+  yaml_file = agent_dir / "root_agent.yaml"
+  assert yaml_file.exists()
+  assert not (agent_dir / "agent.py").exists()
+
+  # Check YAML content
+  yaml_content = yaml_file.read_text()
+  assert "name: root_agent" in yaml_content
+  assert "model: gemini-2.0-flash-001" in yaml_content
+  assert "description: A helpful assistant for user questions." in yaml_content
+
+  # Should create empty __init__.py
+  init_file = agent_dir / "__init__.py"
+  assert init_file.exists()
+  assert init_file.read_text().strip() == ""
+
+  # Should still create .env file
+  env_file = agent_dir / ".env"
+  assert env_file.exists()
+  assert "GOOGLE_API_KEY=test-key" in env_file.read_text()
+
+
 # Prompt helpers
 def test_prompt_for_google_cloud(monkeypatch: pytest.MonkeyPatch) -> None:
   """Prompt should return the project input."""
@@ -174,7 +218,7 @@ def test_prompt_for_google_api_key(monkeypatch: pytest.MonkeyPatch) -> None:
 def test_prompt_for_model_gemini(monkeypatch: pytest.MonkeyPatch) -> None:
   """Selecting option '1' should return the default Gemini model string."""
   monkeypatch.setattr(click, "prompt", lambda *a, **k: "1")
-  assert cli_create._prompt_for_model() == "gemini-2.0-flash-001"
+  assert cli_create._prompt_for_model() == "gemini-2.5-flash"
 
 
 def test_prompt_for_model_other(monkeypatch: pytest.MonkeyPatch) -> None: