Enum Tool 

pub enum Tool {
    Function {
        function_declarations: Vec<FunctionDeclaration>,
    },
    GoogleSearch {
        google_search: GoogleSearchConfig,
    },
}

Tool that can be used by the model

Variants

Function

Function-based tool

Fields

function_declarations: Vec<FunctionDeclaration>

The function declaration for the tool

GoogleSearch

Google Search tool

Fields

google_search: GoogleSearchConfig

The Google Search configuration

Implementations

impl Tool

pub fn new(function_declaration: FunctionDeclaration) -> Self

Create a new tool with a single function declaration

Examples found in repository

examples/google_search_with_functions.rs (line 49)

async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Get API key from environment variable
    let api_key = env::var("GEMINI_API_KEY").expect("GEMINI_API_KEY environment variable not set");

    // Create client
    let client = Gemini::new(api_key);

    println!("--- Meeting Scheduler Function Calling example ---");

    // Define a meeting scheduler function that matches the curl example
    let schedule_meeting = FunctionDeclaration::new(
        "schedule_meeting",
        "Schedules a meeting with specified attendees at a given time and date.",
        FunctionParameters::object()
            .with_property(
                "attendees",
                PropertyDetails::array(
                    "List of people attending the meeting.",
                    PropertyDetails::string("Attendee name"),
                ),
                true,
            )
            .with_property(
                "date",
                PropertyDetails::string("Date of the meeting (e.g., '2024-07-29')"),
                true,
            )
            .with_property(
                "time",
                PropertyDetails::string("Time of the meeting (e.g., '15:00')"),
                true,
            )
            .with_property(
                "topic",
                PropertyDetails::string("The subject or topic of the meeting."),
                true,
            ),
    );

    // Create function tool
    let function_tool = Tool::new(schedule_meeting);

    // Create a request with the tool - matching the curl example
    let response = client
        .generate_content()
        .with_user_message("Schedule a meeting with Bob and Alice for 03/27/2025 at 10:00 AM about the Q3 planning.")
        .with_tool(function_tool.clone())
        .with_function_calling_mode(FunctionCallingMode::Any)
        .execute()
        .await?;

    // Check if there are function calls
    if let Some(function_call) = response.function_calls().first() {
        println!(
            "Function call: {} with args: {}",
            function_call.name, function_call.args
        );

        // Handle the schedule_meeting function
        if function_call.name == "schedule_meeting" {
            let attendees: Vec<String> = function_call.get("attendees")?;
            let date: String = function_call.get("date")?;
            let time: String = function_call.get("time")?;
            let topic: String = function_call.get("topic")?;

            println!("Scheduling meeting:");
            println!("  Attendees: {:?}", attendees);
            println!("  Date: {}", date);
            println!("  Time: {}", time);
            println!("  Topic: {}", topic);

            // Simulate scheduling the meeting
            let meeting_id = format!(
                "meeting_{}",
                std::time::SystemTime::now()
                    .duration_since(std::time::UNIX_EPOCH)
                    .unwrap()
                    .as_secs()
            );

            let function_response = json!({
                "success": true,
                "meeting_id": meeting_id,
                "message": format!("Meeting '{}' scheduled for {} at {} with {:?}", topic, date, time, attendees)
            });

            // Create conversation with function response
            let mut conversation = client.generate_content();

            // 1. Add original user message
            conversation = conversation
                .with_user_message("Schedule a meeting with Bob and Alice for 03/27/2025 at 10:00 AM about the Q3 planning.");

            // 2. Add model message with function call
            let model_function_call =
                FunctionCall::new("schedule_meeting", function_call.args.clone());
            let model_content = Content::function_call(model_function_call).with_role(Role::Model);
            let model_message = Message {
                content: model_content,
                role: Role::Model,
            };
            conversation = conversation.with_message(model_message);

            // 3. Add function response
            conversation =
                conversation.with_function_response("schedule_meeting", function_response);

            // Execute final request
            let final_response = conversation.execute().await?;

            println!("Final response: {}", final_response.text());
        } else {
            println!("Unknown function call: {}", function_call.name);
        }
    } else {
        println!("No function calls in the response.");
        println!("Direct response: {}", response.text());
    }

    Ok(())
}

pub fn with_functions(function_declarations: Vec<FunctionDeclaration>) -> Self

Create a new tool with multiple function declarations

Examples found in repository

examples/tools.rs (line 53)

async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Get API key from environment variable
    let api_key = env::var("GEMINI_API_KEY").expect("GEMINI_API_KEY environment variable not set");

    // Create client
    let client = Gemini::new(api_key);

    println!("--- Tools example with multiple functions ---");

    // Define a weather function
    let get_weather = FunctionDeclaration::new(
        "get_weather",
        "Get the current weather for a location",
        FunctionParameters::object()
            .with_property(
                "location",
                PropertyDetails::string("The city and state, e.g., San Francisco, CA"),
                true,
            )
            .with_property(
                "unit",
                PropertyDetails::enum_type("The unit of temperature", ["celsius", "fahrenheit"]),
                false,
            ),
    );

    // Define a calculator function
    let calculate = FunctionDeclaration::new(
        "calculate",
        "Perform a calculation",
        FunctionParameters::object()
            .with_property(
                "operation",
                PropertyDetails::enum_type(
                    "The mathematical operation to perform",
                    ["add", "subtract", "multiply", "divide"],
                ),
                true,
            )
            .with_property("a", PropertyDetails::number("The first number"), true)
            .with_property("b", PropertyDetails::number("The second number"), true),
    );

    // Create a tool with multiple functions
    let tool = Tool::with_functions(vec![get_weather, calculate]);

    // Create a request with tool functions
    let response = client
        .generate_content()
        .with_system_prompt(
            "You are a helpful assistant that can check weather and perform calculations.",
        )
        .with_user_message("What's 42 times 12?")
        .with_tool(tool)
        .with_function_calling_mode(FunctionCallingMode::Any)
        .execute()
        .await?;

    // Process function calls
    if let Some(function_call) = response.function_calls().first() {
        println!(
            "Function call: {} with args: {}",
            function_call.name, function_call.args
        );

        // Handle different function calls
        match function_call.name.as_str() {
            "calculate" => {
                let operation: String = function_call.get("operation")?;
                let a: f64 = function_call.get("a")?;
                let b: f64 = function_call.get("b")?;

                println!("Calculation: {} {} {}", a, operation, b);

                let result = match operation.as_str() {
                    "add" => a + b,
                    "subtract" => a - b,
                    "multiply" => a * b,
                    "divide" => a / b,
                    _ => panic!("Unknown operation"),
                };

                let function_response = json!({
                    "result": result,
                })
                .to_string();

                // Based on the curl example, we need to structure the conversation properly:
                // 1. A user message with the original query
                // 2. A model message containing the function call
                // 3. A user message containing the function response

                // Construct conversation following the exact curl pattern
                let mut conversation = client.generate_content();

                // 1. Add user message with original query and system prompt
                conversation = conversation
                    .with_system_prompt("You are a helpful assistant that can check weather and perform calculations.")
                    .with_user_message("What's 42 times 12?");

                // 2. Create model content with function call
                let model_content = Content::function_call((*function_call).clone());

                // Add as model message
                let model_message = Message {
                    content: model_content,
                    role: Role::Model,
                };
                conversation = conversation.with_message(model_message);

                // 3. Add user message with function response
                conversation =
                    conversation.with_function_response_str("calculate", function_response)?;

                // Execute the request
                let final_response = conversation.execute().await?;

                println!("Final response: {}", final_response.text());
            }
            "get_weather" => {
                let location: String = function_call.get("location")?;
                let unit = function_call
                    .get::<String>("unit")
                    .unwrap_or_else(|_| String::from("celsius"));

                println!("Weather request for: {}, Unit: {}", location, unit);

                let weather_response = json!({
                    "temperature": 22,
                    "unit": unit,
                    "condition": "sunny"
                })
                .to_string();

                // Based on the curl example, we need to structure the conversation properly:
                // 1. A user message with the original query
                // 2. A model message containing the function call
                // 3. A user message containing the function response

                // Construct conversation following the exact curl pattern
                let mut conversation = client.generate_content();

                // 1. Add user message with original query and system prompt
                conversation = conversation
                    .with_system_prompt("You are a helpful assistant that can check weather and perform calculations.")
                    .with_user_message("What's 42 times 12?");

                // 2. Create model content with function call
                let model_content = Content::function_call((*function_call).clone());

                // Add as model message
                let model_message = Message {
                    content: model_content,
                    role: Role::Model,
                };
                conversation = conversation.with_message(model_message);

                // 3. Add user message with function response
                conversation =
                    conversation.with_function_response_str("get_weather", weather_response)?;

                // Execute the request
                let final_response = conversation.execute().await?;

                println!("Final response: {}", final_response.text());
            }
            _ => println!("Unknown function"),
        }
    } else {
        println!("No function calls in the response.");
        println!("Response: {}", response.text());
    }

    Ok(())
}

pub fn google_search() -> Self

Create a new Google Search tool

Examples found in repository

examples/google_search.rs (line 15)

async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Get API key from environment variable
    let api_key = env::var("GEMINI_API_KEY").expect("GEMINI_API_KEY environment variable not set");

    // Create client
    let client = Gemini::new(api_key);

    println!("--- Google Search tool example ---");

    // Create a Google Search tool
    let google_search_tool = Tool::google_search();

    // Create a request with Google Search tool
    let response = client
        .generate_content()
        .with_user_message("What is the current Google stock price?")
        .with_tool(google_search_tool)
        .execute()
        .await?;

    println!("Response: {}", response.text());

    Ok(())
}

examples/curl_google_search.rs (line 44)

async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Get API key from environment variable
    let api_key = env::var("GEMINI_API_KEY").expect("GEMINI_API_KEY environment variable not set");

    println!("--- Curl equivalent with Google Search tool ---");

    // This is equivalent to the curl example:
    // curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-2.0-flash:generateContent?key=$GEMINI_API_KEY" \
    //   -H "Content-Type: application/json" \
    //   -d '{
    //       "contents": [
    //           {
    //               "parts": [
    //                   {"text": "What is the current Google stock price?"}
    //               ]
    //           }
    //       ],
    //       "tools": [
    //           {
    //               "google_search": {}
    //           }
    //       ]
    //   }'

    // Create client
    let client = Gemini::new(api_key);

    // Create a content part that matches the JSON in the curl example
    let text_part = Part::Text {
        text: "What is the current Google stock price?".to_string(),
        thought: None,
    };

    let content = Content {
        parts: vec![text_part].into(),
        role: None,
    };

    // Create a Google Search tool
    let google_search_tool = Tool::google_search();

    // Add the content and tool directly to the request
    // This exactly mirrors the JSON structure in the curl example
    let mut content_builder = client.generate_content();
    content_builder.contents.push(content);
    content_builder = content_builder.with_tool(google_search_tool);

    let response = content_builder.execute().await?;

    println!("Response: {}", response.text());

    Ok(())
}

Trait Implementations

impl Clone for Tool

fn clone(&self) -> Tool

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Tool

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Tool

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for Tool

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.