Frontend Tools
Create frontend tools and use them within your Agno agent.
What is this?
Frontend tools enable you to define client-side functions that your Agno agent can invoke, with execution happening entirely in the user's browser. When your agent calls a frontend tool, the logic runs on the client side, giving you direct access to the frontend environment.
This can be utilized for to let your agent control the UI, generative UI, or for Human-in-the-loop interactions.
In this guide, we cover the use of frontend tools driving and interacting with the UI.
When should I use this?
Use frontend tools when you need your agent to interact with client-side primitives such as:
- Reading or modifying React component state
- Accessing browser APIs like localStorage, sessionStorage, or cookies
- Triggering UI updates or animations
- Interacting with third-party frontend libraries
- Performing actions that require the user's immediate browser context
Implementation
Run and connect your agent
You'll need to run your agent and connect it to CopilotKit before proceeding.
If you don't already have CopilotKit and your agent connected, choose one of the following options:
Create a frontend tool
First, you'll need to create a frontend tool using the useFrontendTool hook. Here's a simple one to get you started that says hello to the user.
import { useFrontendTool } from "@copilotkit/react-core"
export function Page() {
// ...
useFrontendTool({
name: "sayHello",
description: "Say hello to the user",
parameters: [
{
name: "name",
type: "string",
description: "The name of the user to say hello to",
required: true,
},
],
handler: async ({ name }) => {
alert(`Hello, ${name}!`);
},
});
// ...
}Define the frontend tool in your Agno agent
Now, we'll need to modify the agent to access these frontend tools.
In your Agno agent, define a tool with the @tool(external_execution=True) decorator. This tells Agno that the tool will be executed externally (on the frontend).
from agno.tools import tool
@tool(external_execution=True)
def sayHello(name: str):
"""
Say hello to the user.
Args:
name: The name of the user to say hello to
"""Register the tool with your agent:
from agno.agent import Agent
from agno.models.openai import OpenAIChat
from agno.os import AgentOS
from agno.os.interfaces.agui import AGUI
from tools.frontend import sayHello
agent = Agent(
model=OpenAIChat(id="gpt-4o"),
tools=[sayHello],
description="A helpful assistant that can answer questions and provide information.",
instructions="Be helpful and friendly. Format your responses using markdown where appropriate.",
)
agent_os = AgentOS(agents=[agent], interfaces=[AGUI(agent=agent)])
app = agent_os.get_app()Give it a try!
You've now given your agent the ability to directly call any frontend tools you've defined. These tools will be available to the agent where they can be used as needed.
