Step 2: Add Tools

Define a tool as any method with a [Description] attribute:

using System.ComponentModel;

[Description("Get the weather for a given location.")]
static string GetWeather([Description("The location to get the weather for.")] string location)
    => $"The weather in {location} is cloudy with a high of 15°C.";

Create an agent with the tool:

using System;
using Azure.AI.Projects;
using Azure.Identity;
using Microsoft.Agents.AI;
using Microsoft.Extensions.AI;

var endpoint = Environment.GetEnvironmentVariable("AZURE_OPENAI_ENDPOINT")
    ?? throw new InvalidOperationException("Set AZURE_OPENAI_ENDPOINT");
var deploymentName = Environment.GetEnvironmentVariable("AZURE_OPENAI_DEPLOYMENT_NAME") ?? "gpt-4o-mini";

AIAgent agent = new AIProjectClient(new Uri(endpoint), new DefaultAzureCredential())
    .AsAIAgent(
        model: deploymentName,
        instructions: "You are a helpful assistant.",
        tools: [AIFunctionFactory.Create(GetWeather)]);

The agent will automatically call your tool when relevant:

Console.WriteLine(await agent.RunAsync("What is the weather like in Amsterdam?"));

The complete sample defines a tool with the @tool decorator, creates an agent with the tool, and runs the agent:

# Copyright (c) Microsoft. All rights reserved.

import asyncio
from random import randint
from typing import Annotated

from agent_framework import Agent, tool
from agent_framework.foundry import FoundryChatClient
from azure.identity import AzureCliCredential
from pydantic import Field

"""
Add Tools — Give your agent a function tool

This sample shows how to define a function tool with the @tool decorator
and wire it into an agent so the model can call it.
"""


# <define_tool>
# NOTE: approval_mode="never_require" is for sample brevity.
# Use "always_require" in production for user confirmation before tool execution.
# For tools processing untrusted external data or performing privileged operations,
# review the Agent Safety guidance at
# https://learn.microsoft.com/en-us/agent-framework/concepts/agents/safety
# and see samples/02-agents/security/email_security_example.py for SecureAgentConfig
# and quarantined_llm defense patterns.
@tool(approval_mode="never_require")
def get_weather(
    location: Annotated[str, Field(description="The location to get the weather for.")],
) -> str:
    """Get the weather for a given location."""
    conditions = ["sunny", "cloudy", "rainy", "stormy"]
    return f"The weather in {location} is {conditions[randint(0, 3)]} with a high of {randint(10, 30)}°C."


# </define_tool>


async def main() -> None:
    client = FoundryChatClient(
        project_endpoint="https://your-account.services.ai.azure.com/api/projects/your-project",
        model="gpt-4o",
        credential=AzureCliCredential(),
    )

    # <create_agent_with_tools>
    agent = Agent(
        client=client,
        name="WeatherAgent",
        instructions="You are a helpful weather agent. Use the get_weather tool to answer questions.",
        tools=[get_weather],
    )
    # </create_agent_with_tools>

    # <run_agent>
    result = await agent.run("What's the weather like in Seattle?")
    print(f"Agent: {result}")
    # </run_agent>


if __name__ == "__main__":
    asyncio.run(main())

Define a tool using functool:

import (
    "context"
    "fmt"

    "github.com/microsoft/agent-framework-go/tool"
    "github.com/microsoft/agent-framework-go/tool/functool"
)

var weatherTool = functool.MustNew(functool.Config{
    Name:        "weather",
    Description: "Get the current weather for a given location",
}, func(_ context.Context, location string) (string, error) {
    return fmt.Sprintf("The weather in %s is cloudy with a high of 15°C.", location), nil
})

Create an agent with the tool:

a := foundryprovider.NewAgent(
    endpoint,
    token,
    foundryprovider.ModelDeployment(model),
    foundryprovider.AgentConfig{
        Instructions: "You are a helpful assistant",
        Config: agent.Config{
            Tools: []tool.Tool{weatherTool},
        },
    },
)

The agent will automatically call your tool when relevant:

resp, err := a.RunText(ctx, "What is the weather like in Amsterdam?").Collect()
fmt.Println(resp, err)