feat: Update AgentEvaluator to handle async ADK agent definitions

AgentEvaluator should recognize root_agent and get_agent_async as valid structures for ADK agent definitions.

PiperOrigin-RevId: 819976635

src/google/adk/evaluation/agent_evaluator.py

@@ -118,7 +118,7 @@ class AgentEvaluator:
     Args:
       agent_module: The path to python module that contains the definition of
         the agent. There is convention in place here, where the code is going to
-        look for 'root_agent' in the loaded module.
+        look for 'root_agent' or `get_agent_async` in the loaded module.
       eval_set: The eval set.
       criteria: Evauation criterias, a dictionary of metric names to their
         respective thresholds. This field is deprecated.
@@ -144,7 +144,7 @@ class AgentEvaluator:
     if eval_config is None:
       raise ValueError("`eval_config` is required.")
 
-    agent_for_eval = AgentEvaluator._get_agent_for_eval(
+    agent_for_eval = await AgentEvaluator._get_agent_for_eval(
         module_name=agent_module, agent_name=agent_name
     )
     eval_metrics = get_eval_metrics_from_config(eval_config)
@@ -200,7 +200,7 @@ class AgentEvaluator:
     Args:
       agent_module: The path to python module that contains the definition of
         the agent. There is convention in place here, where the code is going to
-        look for 'root_agent' in the loaded module.
+        look for 'root_agent' or 'get_agent_async' in the loaded module.
       eval_dataset_file_path_or_dir: The eval data set. This can be either a
         string representing full path to the file containing eval dataset, or a
         directory that is recursively explored for all files that have a
@@ -466,12 +466,26 @@ class AgentEvaluator:
     return "\n".join([str(t) for t in tool_calls])
 
   @staticmethod
-  def _get_agent_for_eval(
+  async def _get_agent_for_eval(
       module_name: str, agent_name: Optional[str] = None
   ) -> BaseAgent:
     module_path = f"{module_name}"
     agent_module = importlib.import_module(module_path)
-    root_agent = agent_module.agent.root_agent
+    print(dir(agent_module))
+    if hasattr(agent_module, "agent"):
+      if hasattr(agent_module.agent, "root_agent"):
+        root_agent = agent_module.agent.root_agent
+      elif hasattr(agent_module.agent, "get_agent_async"):
+        root_agent, _ = await agent_module.agent.get_agent_async()
+      else:
+        raise ValueError(
+            f"Module {module_name} does not have a root_agent or"
+            " get_agent_async method."
+        )
+    else:
+      raise ValueError(
+          f"Module {module_name} does not have a member named `agent`."
+      )
 
     agent_for_eval = root_agent
     if agent_name:

tests/integration/fixture/hello_world_agent_async/__init__.py

@@ -0,0 +1,15 @@
+# Copyright 2025 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.
+
+from . import agent

tests/integration/fixture/hello_world_agent_async/agent.py

@@ -0,0 +1,104 @@
+# Copyright 2025 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.
+
+# Hello world agent from agent 1.0 revised to be defined with get_agent_async
+# instead of root_agent - https://colab.sandbox.google.com/drive/1Zq-nqmgK0nCERCv8jKIaoeTTgbNn6oSo?resourcekey=0-GYaz9pFT4wY8CI8Cvjy5GA#scrollTo=u3X3XwDOaCv9
+import contextlib
+import random
+from typing import Optional
+
+from google.adk import Agent
+from google.adk.agents import llm_agent
+from google.genai import types
+
+
+def roll_die(sides: int) -> int:
+  """Roll a die and return the rolled result.
+
+  Args:
+    sides: The integer number of sides the die has.
+
+  Returns:
+    An integer of the result of rolling the die.
+  """
+  return random.randint(1, sides)
+
+
+def check_prime(nums: list[int]) -> list[str]:
+  """Check if a given list of numbers are prime.
+
+  Args:
+    nums: The list of numbers to check.
+
+  Returns:
+    A str indicating which number is prime.
+  """
+  primes = set()
+  for number in nums:
+    number = int(number)
+    if number <= 1:
+      continue
+    is_prime = True
+    for i in range(2, int(number**0.5) + 1):
+      if number % i == 0:
+        is_prime = False
+        break
+    if is_prime:
+      primes.add(number)
+  return (
+      'No prime numbers found.'
+      if not primes
+      else f"{', '.join(str(num) for num in primes)} are prime numbers."
+  )
+
+
+async def get_agent_async() -> (
+    tuple[llm_agent.LlmAgent, Optional[contextlib.AsyncExitStack]]
+):
+  """Returns the root agent."""
+  root_agent = Agent(
+      model='gemini-2.0-flash-001',
+      name='data_processing_agent',
+      instruction="""
+      You roll dice and answer questions about the outcome of the dice rolls.
+      You can roll dice of different sizes.
+      You can use multiple tools in parallel by calling functions in parallel(in one request and in one round).
+      The only things you do are roll dice for the user and discuss the outcomes.
+      It is ok to discuss previous dice roles, and comment on the dice rolls.
+      When you are asked to roll a die, you must call the roll_die tool with the number of sides. Be sure to pass in an integer. Do not pass in a string.
+      You should never roll a die on your own.
+      When checking prime numbers, call the check_prime tool with a list of integers. Be sure to pass in a list of integers. You should never pass in a string.
+      You should not check prime numbers before calling the tool.
+      When you are asked to roll a die and check prime numbers, you should always make the following two function calls:
+      1. You should first call the roll_die tool to get a roll. Wait for the function response before calling the check_prime tool.
+      2. After you get the function response from roll_die tool, you should call the check_prime tool with the roll_die result.
+        2.1 If user asks you to check primes based on previous rolls, make sure you include the previous rolls in the list.
+      3. When you respond, you must include the roll_die result from step 1.
+      You should always perform the previous 3 steps when asking for a roll and checking prime numbers.
+      You should not rely on the previous history on prime results.
+    """,
+      tools=[
+          roll_die,
+          check_prime,
+      ],
+      generate_content_config=types.GenerateContentConfig(
+          safety_settings=[
+              types.SafetySetting(  # avoid false alarm about rolling dice.
+                  category=types.HarmCategory.HARM_CATEGORY_DANGEROUS_CONTENT,
+                  threshold=types.HarmBlockThreshold.OFF,
+              ),
+          ]
+      ),
+  )
+  return root_agent, None

tests/integration/fixture/hello_world_agent_async/roll_die.test.json

@@ -0,0 +1,55 @@
+{
+  "eval_set_id": "56540925-a5ff-49fe-a4e1-589fe78066f2",
+  "name": "56540925-a5ff-49fe-a4e1-589fe78066f2",
+  "description": null,
+  "eval_cases": [
+    {
+      "eval_id": "tests/integration/fixture/hello_world_agent_async/roll_die.test.json",
+      "conversation": [
+        {
+          "invocation_id": "b01f67f0-9f23-44d6-bbe4-36ea235cb9fb",
+          "user_content": {
+            "parts": [
+              {
+                "video_metadata": null,
+                "thought": null,
+                "code_execution_result": null,
+                "executable_code": null,
+                "file_data": null,
+                "function_call": null,
+                "function_response": null,
+                "inline_data": null,
+                "text": "Hi who are you?"
+              }
+            ],
+            "role": "user"
+          },
+          "final_response": {
+            "parts": [
+              {
+                "video_metadata": null,
+                "thought": null,
+                "code_execution_result": null,
+                "executable_code": null,
+                "file_data": null,
+                "function_call": null,
+                "function_response": null,
+                "inline_data": null,
+                "text": "I am a data processing agent. I can roll dice and check if the results are prime numbers. What would you like me to do? \n"
+              }
+            ],
+            "role": "model"
+          },
+          "intermediate_data": {
+            "tool_uses": [],
+            "intermediate_responses": []
+          },
+          "creation_timestamp": 1747341775.8937013
+        }
+      ],
+      "session_input": null,
+      "creation_timestamp": 1747341775.8937826
+    }
+  ],
+  "creation_timestamp": 1747341775.8937957
+}

tests/integration/fixture/hello_world_agent_async/test_config.json

@@ -0,0 +1,6 @@
+{
+  "criteria": {
+    "tool_trajectory_avg_score": 1.0,
+    "response_match_score": 0.5
+  }
+}

tests/integration/test_single_agent.py

@@ -23,3 +23,14 @@ async def test_eval_agent():
       eval_dataset_file_path_or_dir="tests/integration/fixture/home_automation_agent/simple_test.test.json",
       num_runs=4,
   )
+
+
+@pytest.mark.asyncio
+async def test_eval_agent_async():
+  await AgentEvaluator.evaluate(
+      agent_module="tests.integration.fixture.hello_world_agent_async",
+      eval_dataset_file_path_or_dir=(
+          "tests/integration/fixture/hello_world_agent_async/roll_die.test.json"
+      ),
+      num_runs=4,
+  )