diff --git a/Sources/Passes/DTOs/PassJSON.swift b/Sources/Passes/DTOs/PassJSON.swift
new file mode 100644
index 0000000..50fcd21
--- /dev/null
+++ b/Sources/Passes/DTOs/PassJSON.swift
@@ -0,0 +1,99 @@
+//
+//  PassJSON.swift
+//  PassKit
+//
+//  Created by Francesco Paolo Severino on 28/06/24.
+//
+
+/// A protocol that defines the structure of a `pass.json` file.
+/// 
+/// > Tip: See the [`Pass`](https://developer.apple.com/documentation/walletpasses/pass) object to understand the keys.
+public protocol PassJSON: Encodable {
+    /// A short description that iOS accessibility technologies use for a pass.
+    var description: String { get set }
+
+    /// The version of the file format. The value must be 1.
+    var formatVersion: Int { get }
+
+    /// The name of the organization.
+    var organizationName: String { get set }
+
+    /// The pass type identifier that’s registered with Apple.
+    /// 
+    /// The value must be the same as the distribution certificate used to sign the pass.
+    var passTypeIdentifier: String { get set }
+
+    /// An alphanumeric serial number.
+    /// 
+    /// The combination of the serial number and pass type identifier must be unique for each pass.
+    var serialNumber: String { get set }
+
+    /// The Team ID for the Apple Developer Program account that registered the pass type identifier.
+    var teamIdentifier: String { get set }
+}
+
+public extension PassJSON {
+    var formatVersion: Int {
+        return 1
+    }
+}
+
+/// A protocol that represents the information to display in a field on a pass.
+///
+/// > Tip: See the [`PassFieldContent`](https://developer.apple.com/documentation/walletpasses/passfieldcontent) object to understand the keys.
+public protocol PassFieldContent: Encodable {
+    /// A unique key that identifies a field in the pass; for example, `departure-gate`.
+    var key: String { get set }
+
+    /// The value to use for the field; for example, 42. 
+    /// 
+    /// A date or time value must include a time zone.
+    var value: String { get set }
+}
+
+/// A protocol that represents the groups of fields that display the information for a boarding pass.
+/// 
+/// > Tip: See the [`Pass.BoardingPass`](https://developer.apple.com/documentation/walletpasses/pass/boardingpass) object to understand the keys.
+public protocol BoardingPass: Encodable {
+    /// The type of transit for a boarding pass.
+    /// 
+    /// This key is invalid for other types of passes.
+    /// 
+    /// The system may use the value to display more information,
+    /// such as showing an airplane icon for the pass on watchOS when the value is set to `PKTransitTypeAir`.
+    var transitType: TransitType { get set }
+}
+
+/// The type of transit for a boarding pass.
+public enum TransitType: String {
+    case air = "PKTransitTypeAir"
+    case boat = "PKTransitTypeBoat"
+    case bus = "PKTransitTypeBus"
+    case generic = "PKTransitTypeGeneric"
+    case train = "PKTransitTypeTrain"
+}
+
+/// A protocol that represents a barcode on a pass.
+/// 
+/// > Tip: See the [`Pass.Barcodes`](https://developer.apple.com/documentation/walletpasses/pass/barcodes) object to understand the keys.
+public protocol Barcodes: Encodable {
+    /// The format of the barcode.
+    /// 
+    /// The barcode format `PKBarcodeFormatCode128` isn’t supported for watchOS.
+    var format: BarcodeFormat { get set }
+
+    /// The message or payload to display as a barcode.
+    var message: String { get set }
+
+    /// The IANA character set name of the text encoding to use to convert message
+    /// from a string representation to a data representation that the system renders as a barcode, such as `iso-8859-1`.
+    var messageEncoding: String { get set }
+}
+
+/// The format of the barcode.
+public enum BarcodeFormat: String {
+    case pdf417 = "PKBarcodeFormatPDF417"
+    case qr = "PKBarcodeFormatQR"
+    case aztec = "PKBarcodeFormatAztec"
+    case code128 = "PKBarcodeFormatCode128"
+}
diff --git a/Sources/Passes/PassesDelegate.swift b/Sources/Passes/PassesDelegate.swift
index 1e8f7d8..eb6712f 100644
--- a/Sources/Passes/PassesDelegate.swift
+++ b/Sources/Passes/PassesDelegate.swift
@@ -68,7 +68,7 @@ public protocol PassesDelegate: AnyObject, Sendable {
     ///   - encoder: The `JSONEncoder` which you should use.
     /// - Returns: The encoded pass JSON data.
     ///
-    /// > Tip: See the [Pass](https://developer.apple.com/documentation/walletpasses/pass) object to understand the keys.
+    /// > Tip: See the [`Pass`](https://developer.apple.com/documentation/walletpasses/pass) object to understand the keys.
     func encode<P: PassModel>(pass: P, db: any Database, encoder: JSONEncoder) async throws -> Data
 
     /// Should return a `URL` which points to the template data for the pass.
diff --git a/Sources/Passes/PassesError.swift b/Sources/Passes/PassesError.swift
index a28a089..0c0f34c 100644
--- a/Sources/Passes/PassesError.swift
+++ b/Sources/Passes/PassesError.swift
@@ -1,6 +1,6 @@
 //
 //  PassesError.swift
-//  
+//  PassKit
 //
 //  Created by Scott Grosch on 1/22/20.
 //