Add live web search to a Google ADK agent

Google ADK (Agent Development Kit) is Python-first and treats plain functions as first-class tools — pass any typed function to tools=[...] and the agent can call it. For all five Superhighway tools with autonomous x402 payments, the MCPToolset path is faster to set up.

Two paths

Path 1: MCP via MCPToolset (recommended for autonomous agents)

pip install google-adk mcp

import asyncio, os
from google.adk import Agent, Runner
from google.adk.tools.mcp_tool import MCPToolset
from google.adk.tools.mcp_tool.mcp_session_manager import StdioConnectionParams
from google.adk.sessions import InMemorySessionService
from mcp import StdioServerParameters
from google.genai import types

agent = Agent(
    model="gemini-2.5-flash",
    name="search_agent",
    instruction="You are a research assistant with access to live web search.",
    tools=[
        MCPToolset(
            connection_params=StdioConnectionParams(
                server_params=StdioServerParameters(
                    command="npx",
                    args=["-y", "superhighway-mcp"],
                    env={
                        "AGENT_PRIVATE_KEY": os.environ["AGENT_PRIVATE_KEY"],
                        "X402_NETWORK": "base",
                    },
                )
            )
        )
    ],
)

runner = Runner(
    agent=agent,
    app_name="search_app",
    session_service=InMemorySessionService(),
)

async def main():
    session = await runner.session_service.create_session(
        app_name="search_app", user_id="user1"
    )
    async for event in runner.run_async(
        user_id="user1",
        session_id=session.id,
        new_message=types.Content(
            role="user",
            parts=[types.Part(text="What are the latest developments in AI agent frameworks?")],
        ),
    ):
        if event.is_final_response() and event.content:
            print(event.content.parts[0].text)

asyncio.run(main())

AGENT_PRIVATE_KEY is the private key of a wallet with USDC on Base. Each search call costs $0.001 and is settled automatically via the x402 protocol — no signup, no API key, no human in the loop. The MCPToolset exposes all five tools: web_search, news_search, image_search, scrape, and research.

Path 2: Function tools with an API key

ADK treats any typed Python function with a docstring as a tool — no decorator needed. The type annotations and Args: section of the docstring are the schema the model reads.

pip install google-adk requests

import asyncio, os, requests
from google.adk import Agent, Runner
from google.adk.sessions import InMemorySessionService
from google.genai import types

BASE = "https://superhighway.walls.sh"
HEADERS = {"X-Api-Key": os.environ["SUPERHIGHWAY_API_KEY"]}

def web_search(query: str, limit: int = 5) -> dict:
    """Search the live web for current information.

    Args:
        query: The search query string.
        limit: Maximum number of results to return.

    Returns:
        Search results with titles, URLs, and snippets.
    """
    return requests.get(f"{BASE}/search", params={"q": query, "limit": limit}, headers=HEADERS).json()

def news_search(query: str, limit: int = 5) -> dict:
    """Search for recent news articles about a topic.

    Args:
        query: The news search query.
        limit: Maximum number of articles to return.

    Returns:
        Recent news articles with titles, sources, and summaries.
    """
    return requests.get(f"{BASE}/news", params={"q": query, "limit": limit}, headers=HEADERS).json()

def research(query: str, pages: int = 3) -> dict:
    """Perform deep research by searching and reading multiple web pages.

    Args:
        query: The research topic or question.
        pages: Number of pages to read for synthesis.

    Returns:
        Synthesized research summary from multiple sources.
    """
    return requests.get(f"{BASE}/research", params={"q": query, "pages": pages}, headers=HEADERS).json()

agent = Agent(
    model="gemini-2.5-flash",
    name="search_agent",
    instruction="You are a research assistant with access to live web search.",
    tools=[web_search, news_search, research],
)

runner = Runner(
    agent=agent,
    app_name="search_app",
    session_service=InMemorySessionService(),
)

async def main():
    session = await runner.session_service.create_session(
        app_name="search_app", user_id="user1"
    )
    async for event in runner.run_async(
        user_id="user1",
        session_id=session.id,
        new_message=types.Content(
            role="user",
            parts=[types.Part(text="What changed in the latest Python release?")],
        ),
    ):
        if event.is_final_response() and event.content:
            print(event.content.parts[0].text)

asyncio.run(main())

The key ADK pattern: plain functions are tools. The Args: section of the docstring maps directly to the tool's parameter descriptions — no @tool decorator, no Pydantic model, no class hierarchy needed.

Which tools are available

Full API reference: /openapi.json. Get a free API key or learn the x402 wallet flow.