chore: import upstream snapshot with attribution

contributing/samples/legacy_workflows/simple_sequential_agent/agent.py

@@ -0,0 +1,92 @@
+# 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.
+
+import random
+
+from google.adk.agents.llm_agent import LlmAgent
+from google.adk.agents.sequential_agent import SequentialAgent
+from google.genai import types
+
+
+# --- Roll Die Sub-Agent ---
+def roll_die(sides: int) -> int:
+  """Roll a die and return the rolled result."""
+  return random.randint(1, sides)
+
+
+roll_agent = LlmAgent(
+    name="roll_agent",
+    description="Handles rolling dice of different sizes.",
+    instruction="""
+      You are responsible for rolling dice based on the user's request.
+      When asked to roll a die, you must call the roll_die tool with the number of sides as an integer.
+    """,
+    tools=[roll_die],
+    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,
+            ),
+        ]
+    ),
+)
+
+
+def check_prime(nums: list[int]) -> str:
+  """Check if a given list of numbers are 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."
+  )
+
+
+prime_agent = LlmAgent(
+    name="prime_agent",
+    description="Handles checking if numbers are prime.",
+    instruction="""
+      You are responsible for checking whether numbers are prime.
+      When asked to check primes, you must call the check_prime tool with a list of integers.
+      Never attempt to determine prime numbers manually.
+      Return the prime number results to the root agent.
+    """,
+    tools=[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,
+            ),
+        ]
+    ),
+)
+
+root_agent = SequentialAgent(
+    name="simple_sequential_agent",
+    sub_agents=[roll_agent, prime_agent],
+    # The agents will run in the order provided: roll_agent -> prime_agent
+)