Any LLM feature.
On every iPhone.

import OnDeviceKit

struct Letter: Codable, Sendable {
    var sender: String
    var action: String
    var deadline: String
    var steps: [String]
}

let schema = Schema("Letter") {
    Property("sender", .string, "Who sent it, short")
    Property("action", .choice(["none", "pay", "reply", "sign"]))
    Property("deadline", .date, "Only if the letter names one")
    Property("steps", .list(.string, max: 4), "Tiny steps")
}

// Downloads once, in the background, checked against its SHA-256
let store = ModelStore(.lfm2_2_6B)

let assistant = Assistant<Letter>(
    schema: schema,
    instructions: "Read the letter. Use only facts from it.",
    model: store.readyFile,
    rules: { text in Letter.guess(from: text) }
)

let (letter, tier) = try await assistant.run(scannedText)
// tier: .apple, .local or .rules

import OnDeviceKit

struct Receipt: Codable, Sendable {
    var merchant: String
    var total: Double
    var category: String
    var date: String
}

let schema = Schema("Receipt") {
    Property("merchant", .string)
    Property("total", .number, "The amount paid")
    Property("category", .choice(["groceries", "restaurant",
                                  "transport", "shopping", "other"]))
    Property("date", .date)
}

let assistant = Assistant<Receipt>(
    schema: schema,
    instructions: "Read the receipt text from the camera.",
    model: store.readyFile,
    rules: { Receipt.totalOnly(from: $0) }
)

let (receipt, tier) = try await assistant.run(ocrText)
expenses.add(receipt)

import OnDeviceKit

struct Plan: Codable, Sendable {
    struct Task: Codable, Sendable {
        var title: String
        var due: String
        var priority: Int
    }
    var tasks: [Task]
}

let task = Schema("Task") {
    Property("title", .string, "Short, starts with a verb")
    Property("due", .date)
    Property("priority", .integer(1...3))
}
let schema = Schema("Plan") {
    Property("tasks", .list(.object(task), max: 8))
}

// The transcript comes from Apple's Speech framework
let (plan, tier) = try await Assistant<Plan>(
    schema: schema,
    instructions: "Turn the voice note into tasks.",
    model: store.readyFile
).run(transcript)

import OnDeviceKit

struct Triage: Codable, Sendable {
    var mood: String
    var topic: String
    var urgent: Bool
    var reply: String
}

let schema = Schema("Triage") {
    Property("mood", .choice(["happy", "neutral",
                              "annoyed", "angry"]))
    Property("topic", .choice(["billing", "bug",
                               "feature", "account"]))
    Property("urgent", .boolean)
    Property("reply", .string, "A short, warm first reply")
}

let assistant = Assistant<Triage>(
    schema: schema,
    instructions: "Sort the customer message and draft a reply.",
    model: store.readyFile,
    rules: { Triage.keywords(in: $0) }
)

let (triage, tier) = try await assistant.run(message)