Building Multi-Agent AI Systems

from google.adk.agents import Agent

def lookup_customer(email: str) -> dict:
    "Look up customer account information by email."
    return {"name": "Jane Doe", "plan": "Pro"}

def check_order_status(order_id: str) -> dict:
    "Check the current status of an order."
    return {"order_id": order_id, "status": "shipped"}

support_agent = Agent(
    name="support_agent",
    model="gemini-2.5-flash",
    instruction="You are a helpful customer support agent.",
    tools=[lookup_customer, check_order_status],
)

billing_agent = Agent(
    name="billing_agent",
    model="gemini-2.5-flash",
    description="Handles billing: invoices, payments, refunds.",
    instruction="Help customers with billing issues.",
    tools=[lookup_invoice, process_refund],
)

technical_agent = Agent(
    name="technical_agent",
    model="gemini-2.5-flash",
    description="Handles technical issues: bugs, outages, how-to.",
    instruction="Help customers with technical problems.",
    tools=[search_knowledge_base, check_system_status],
)

root_agent = Agent(
    name="support_router",
    model="gemini-2.5-flash",
    instruction="Route customer queries to the right specialist.",
    sub_agents=[billing_agent, technical_agent],
)

from google.adk.agents import Agent
from google.adk.tools.mcp_tool import McpToolset, StdioConnectionParams
from mcp.client.stdio import StdioServerParameters

supabase_mcp = McpToolset(
    connection_params=StdioConnectionParams(
        server_params=StdioServerParameters(
            command="npx",
            args=["-y", "@supabase/mcp-server-supabase@latest",
                  "--access-token", TOKEN],
        ),
    ),
)

billing_agent = Agent(
    model="gemini-2.5-flash",
    name="billing_agent_mcp",
    instruction="You are a billing specialist with real database access.",
    tools=[supabase_mcp],
)

McpToolset(
    connection_params=StdioConnectionParams(...),
    tool_filter=[
        "read_file",
        "list_directory",
        "search_files",
    ],  # Only these tools available to the agent
)