chore: import upstream snapshot with attribution

contributing/samples/patterns/json_passing_agent/agent.py

@@ -0,0 +1,120 @@
+# 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.
+
+from google.adk import Agent
+from google.adk.agents import sequential_agent
+from google.adk.tools import tool_context
+from pydantic import BaseModel
+
+SequentialAgent = sequential_agent.SequentialAgent
+ToolContext = tool_context.ToolContext
+
+
+# 1. Define the data structure for the pizza order.
+class PizzaOrder(BaseModel):
+  """A data class to hold the details of a pizza order."""
+
+  size: str
+  crust: str
+  toppings: list[str]
+
+
+# 2. Define tools for the order intake agent.
+def get_available_sizes() -> list[str]:
+  """Returns the available pizza sizes."""
+  return ['small', 'medium', 'large']
+
+
+def get_available_crusts() -> list[str]:
+  """Returns the available pizza crusts."""
+  return ['thin', 'thick', 'stuffed']
+
+
+def get_available_toppings() -> list[str]:
+  """Returns the available pizza toppings."""
+  return ['pepperoni', 'mushrooms', 'onions', 'sausage', 'bacon', 'pineapple']
+
+
+# 3. Define the order intake agent.
+# This agent's job is to interact with the user to fill out a PizzaOrder object.
+# It uses the output_schema to structure its response as a JSON object that
+# conforms to the PizzaOrder model.
+order_intake_agent = Agent(
+    name='order_intake_agent',
+    instruction=(
+        "You are a pizza order intake agent. Your goal is to get the user's"
+        ' pizza order. Use the available tools to find out what sizes, crusts,'
+        ' and toppings are available. Once you have all the information,'
+        ' provide it in the requested format. Your output MUST be a JSON object'
+        ' that conforms to the PizzaOrder schema and nothing else.'
+    ),
+    output_key='pizza_order',
+    output_schema=PizzaOrder,
+    tools=[get_available_sizes, get_available_crusts, get_available_toppings],
+)
+
+
+# 4. Define a tool for the order confirmation agent.
+def calculate_price(tool_context: ToolContext) -> str:
+  """Calculates the price of a pizza order and returns a descriptive string."""
+  order_dict = tool_context.state.get('pizza_order')
+  if not order_dict:
+    return "I can't find an order to calculate the price for."
+
+  order = PizzaOrder.model_validate(order_dict)
+
+  price = 0.0
+  if order.size == 'small':
+    price += 8.0
+  elif order.size == 'medium':
+    price += 10.0
+  elif order.size == 'large':
+    price += 12.0
+
+  if order.crust == 'stuffed':
+    price += 2.0
+
+  price += len(order.toppings) * 1.5
+  return f'The total price for your order is ${price:.2f}.'
+
+
+# 5. Define the order confirmation agent.
+# This agent reads the PizzaOrder object from the session state (placed there by
+# the order_intake_agent) and confirms the order with the user.
+order_confirmation_agent = Agent(
+    name='order_confirmation_agent',
+    instruction=(
+        'Confirm the pizza order with the user. The order is in the state'
+        ' variable `pizza_order`. First, use the `calculate_price` tool to get'
+        ' the price. Then, summarize the order details from {pizza_order} and'
+        ' include the price in your summary. For example: "You ordered a large'
+        ' thin crust pizza with pepperoni and mushrooms. The total price is'
+        ' $15.00."'
+    ),
+    tools=[calculate_price],
+)
+
+# 6. Define the root agent as a sequential agent.
+# This agent directs the conversation by running its sub-agents in order.
+root_agent = SequentialAgent(
+    name='pizza_ordering_agent',
+    sub_agents=[
+        order_intake_agent,
+        order_confirmation_agent,
+    ],
+    description=(
+        'This agent is used to order pizza. It will ask the user for their'
+        ' pizza order and then confirm the order with the user.'
+    ),
+)