Tools

import FoundationModels

struct WeatherTool: Tool {
    let name = "get_weather"
    let description = "Returns the current weather for a city."
    let includesSchemaInInstructions = true

    @Generable
    struct Arguments {
        @Guide(description: "The city to look up")
        var city: String
    }

    func call(arguments: Arguments) async throws -> String {
        "Weather for \(arguments.city): 22°C and sunny."
    }
}

let session = LanguageModelSession(
    tools: [WeatherTool()]
)

let response = try await session.respond(
    to: "Quel temps fait-il à Paris ?"
)

print(response.content)

@Generable
struct WeatherResult {
    @Guide(description: "City name")
    var city: String = ""

    @Guide(description: "Current temperature in Celsius")
    var temperature: Int = 0
}

@Generable
struct WeatherAdvice {
    @Guide(description: "Conseil météo en une phrase")
    var summary: String = ""

    @Guide(description: "Tenue recommandée")
    var outfit: String = ""
}

let session = LanguageModelSession(
    tools: [WeatherTool()]
)

let result = try await session.respond(
    to: "À partir de la météo actuelle à Paris, donne un conseil simple.",
    generating: WeatherAdvice.self
)

enum WeatherToolError: LocalizedError {
    case cityNotFound

    var errorDescription: String? {
        switch self {
        case .cityNotFound:
            return "City not found."
        }
    }
}