Allow returning images and files from tool calls

Author: m1guelpf

src/Models/Input.swift

@@ -297,7 +297,7 @@ public extension Input.ListItem {
 	/// - Parameter status: The status of the item. Populated when items are returned via API.
 	/// - Parameter callId: The ID of the computer tool call that produced the output.
 	/// - Parameter output: A JSON string of the output of the function tool call.
-	static func functionCallOutput(id: String? = nil, status: Item.FunctionCall.Status? = nil, callId: String, output: String) -> Self {
+	static func functionCallOutput(id: String? = nil, status: Item.FunctionCall.Status? = nil, callId: String, output: Input.Content) -> Self {
 		.item(Item.Input.functionCallOutput(Item.FunctionCallOutput(id: id, status: status, callId: callId, output: output)))
 	}
 

src/Models/Item.swift

@@ -408,15 +408,15 @@ import MetaCodable
 		public var callId: String
 
 		/// A JSON string of the output of the function tool call.
-		public var output: String
+		public var output: ModelInput.Content
 
 		/// Creates a new function call output.
 		///
 		/// - Parameter id: The unique ID of the function tool call output. Populated when this item is returned via API.
 		/// - Parameter status: The status of the item. Populated when items are returned via API.
 		/// - Parameter callId: The ID of the computer tool call that produced the output.
 		/// - Parameter output: A JSON string of the output of the function tool call.
-		public init(id: String? = nil, status: FunctionCall.Status? = nil, callId: String, output: String) {
+		public init(id: String? = nil, status: FunctionCall.Status? = nil, callId: String, output: ModelInput.Content) {
 			self.id = id
 			self.status = status
 			self.callId = callId
@@ -1210,14 +1210,14 @@ import MetaCodable
 		public var callId: String
 
 		/// The output from the custom tool call generated by your code.
-		public var output: String
+		public var output: ModelInput.Content
 
 		/// Creates a new custom tool call output
 		///
 		/// - Parameter id: The unique ID of the custom tool call output in the OpenAI platform.
 		/// - Parameter callId: The call ID, used to map this custom tool call output to a custom tool call.
 		/// - Parameter output: The output from the custom tool call generated by your code.
-		public init(id: String? = nil, callId: String, output: String) {
+		public init(id: String? = nil, callId: String, output: ModelInput.Content) {
 			self.id = id
 			self.callId = callId
 			self.output = output
@@ -1322,7 +1322,7 @@ public extension Item.Input {
 	/// - Parameter status: The status of the item. Populated when items are returned via API.
 	/// - Parameter callId: The ID of the computer tool call that produced the output.
 	/// - Parameter output: A JSON string of the output of the function tool call.
-	static func functionCallOutput(id: String? = nil, status: Item.FunctionCall.Status? = nil, callId: String, output: String) -> Self {
+	static func functionCallOutput(id: String? = nil, status: Item.FunctionCall.Status? = nil, callId: String, output: Input.Content) -> Self {
 		.functionCallOutput(Item.FunctionCallOutput(id: id, status: status, callId: callId, output: output))
 	}
 
@@ -1436,7 +1436,7 @@ public extension Item.Input {
 	/// - Parameter id: The unique ID of the custom tool call output in the OpenAI platform.
 	/// - Parameter callId: The call ID, used to map this custom tool call output to a custom tool call.
 	/// - Parameter output: The output from the custom tool call generated by your code.
-	static func customToolCallOutput(id: String? = nil, callId: String, output: String) -> Self {
+	static func customToolCallOutput(id: String? = nil, callId: String, output: ModelInput.Content) -> Self {
 		.customToolCallOutput(Item.CustomToolCallOutput(id: id, callId: callId, output: output))
 	}
 }

src/Protocol/Toolable.swift

@@ -49,9 +49,22 @@ package extension Toolable {
 		let output = try await call(parameters: parameters)
 
 		if output is NullableVoid { return nil }
+
+		if output is String {
+			return Item.FunctionCallOutput(callId: functionCall.callId, output: .text(output as! String))
+		}
+
+		if output is Input.Content {
+			return Item.FunctionCallOutput(callId: functionCall.callId, output: output as! ModelInput.Content)
+		}
+
+		if output is Input.Content.ContentItem {
+			return Item.FunctionCallOutput(callId: functionCall.callId, output: .list([output as! ModelInput.Content.ContentItem]))
+		}
+
 		return try Item.FunctionCallOutput(
 			callId: functionCall.callId,
-			output: encoder.encodeToString(output)
+			output: .text(encoder.encodeToString(output))
 		)
 	}
 }