First write doesn't trigger Face ID authentication

[henlund]

I'm using Face ID authentication to protect items in the keychain. However, the authentication dialog is not triggered when a new value is written. Only when reading and overwriting the value for the same id, the dialog is displayed. Is this intended behaviour?
Also the string passed to .authenticationPrompt() is never displayed. Where is it supposed to show up?

func save(data: String, id: String) async {
    try? keychain
      .accessibility(.whenPasscodeSetThisDeviceOnly, authenticationPolicy: [.biometryAny])
      .authenticationPrompt("This text is never shown")
      .set(data, key: id)
  }

  func load(id: String) async -> String? {
    try? keychain
      .authenticationPrompt("This text is never shown")
      .get(id)
  }