When using App Intents, I can edit already existing SwiftData items, but I cannot insert new ones. Below are the two app intents I’ve used, both function in their entirety other than the model context insertion at the end of the second one.

struct LinkViewedIntent: AppIntent {
    static var title: LocalizedStringResource = "Mark Link Viewed"
    
    @Parameter(title: "Link")
    var link: LinkEntity?
    
    init(link: Link) {
        self.link = LinkEntity(link: link)
    }
    
    init() {}
    
    func perform() async throws -> some IntentResult & ProvidesDialog {
        let entities = try await LinkEntityQuery().suggestedEntities().filter({$0.viewed == false})
        guard !entities.isEmpty else {
            return .result(dialog: "There are no unviewed links to mark.")
        }
        var enteredLink: LinkEntity
        if let link = link {
            enteredLink = link
        } else {
            enteredLink = try await $link.requestDisambiguation(
                among: LinkEntityQuery().suggestedEntities(),
                dialog: "Which link would you like to mark viewed?"
            )
        }
        let context = ModelContext(ConfigureModelContainer())
        let links = try? context.fetch(FetchDescriptor<Link>())
        guard let link = links?.filter({ $0.id == enteredLink.id }).first else {
            return .result(dialog: "An Error Occured")
        }
        if link.viewed == true {
            return .result(dialog: "Link is already viewed")
        }
        link.viewed = true
        try context.save()
        
        return .result(dialog: "Okay, (enteredLink.name ?? enteredLink.link) has been marked as viewed.")
    }
    
    static var parameterSummary: some ParameterSummary {
            Summary("Mark (.$link) as viewed.")
    }
}

struct SaveLinkIntent: AppIntent {
    static var title: LocalizedStringResource = "Save Link"
    
    @Parameter(title: "URL")
    var url: URL?
    
    func perform() async throws -> some IntentResult & ProvidesDialog {
        let modelContext = ModelContext(ConfigureModelContainer())
        var fullurl: URL
        if let url = url {
            fullurl = url
        } else {
            fullurl = try await $url.requestValue()
        }
        print(fullurl.absoluteString)
        guard let link = await makeLink(address: fullurl.absoluteString) else {
            return .result(dialog: "")
        }
        modelContext.insert(link)
        return .result(dialog: "I've added (link.metadata?.title ?? link.address) to Memento")
        
    }
}

The first one works completely as expected, the second one makes the link object and sends the correct dialog at the end but when I check back in the app, the link hasn’t been added.