Update

Author: intitni

Pro

@@ -8,7 +8,7 @@ public protocol CallbackEvent {
 public struct CallbackEvents {
     public struct UnTypedEvent: CallbackEvent {
         public var info: String
-        init(info: String) {
+        public init(info: String) {
             self.info = info
         }
     }

Tool/Sources/LangChain/Callback.swift

@@ -0,0 +1,70 @@
+import Foundation
+import Logger
+import OpenAIService
+
+public class CombineAnswersChain: Chain {
+    public struct Input: Decodable {
+        public var question: String
+        public var answers: [String]
+        public init(question: String, answers: [String]) {
+            self.question = question
+            self.answers = answers
+        }
+    }
+
+    public typealias Output = String
+    public let chatModelChain: ChatModelChain<Input>
+
+    public init(
+        configuration: ChatGPTConfiguration = UserPreferenceChatGPTConfiguration(),
+        extraInstructions: String = ""
+    ) {
+        chatModelChain = .init(
+            chatModel: OpenAIChat(
+                configuration: configuration.overriding {
+                    $0.runFunctionsAutomatically = false
+                },
+                memory: nil,
+                stream: false
+            ),
+            stops: ["Observation:"],
+            promptTemplate: { input in
+                [
+                    .init(
+                        role: .system,
+                        content: """
+                        You are a helpful assistant.
+                        Your job is to combine multiple answers from different sources to one question.
+                        \(extraInstructions)
+                        """
+                    ),
+                    .init(role: .user, content: """
+                    Question: \(input.question)
+
+                    Answers:
+                    \(input.answers.joined(separator: "\n\(String(repeating: "-", count: 32))\n"))
+
+                    What is the combined answer?
+                    """),
+                ]
+            }
+        )
+    }
+
+    public func callLogic(
+        _ input: Input,
+        callbackManagers: [CallbackManager]
+    ) async throws -> String {
+        let output = try await chatModelChain.call(input, callbackManagers: callbackManagers)
+        return await parseOutput(output)
+    }
+
+    public func parseOutput(_ message: ChatMessage) async -> String {
+        return message.content ?? "No answer."
+    }
+
+    public func parseOutput(_ output: String) -> String {
+        output
+    }
+}
+

Tool/Sources/LangChain/Chains/CombineAnswersChain.swift

@@ -63,9 +63,8 @@ public class StructuredOutputChatModelChain<Output: Decodable>: Chain {
 
     public init(
         configuration: ChatGPTConfiguration = UserPreferenceChatGPTConfiguration(),
-        tools: [AgentTool] = [],
         endFunction: EndFunction,
-        extraSystemPrompt: String = ""
+        promptTemplate: ((String) -> [ChatMessage])? = nil
     ) {
         functionProvider = .init(
             endFunction: endFunction
@@ -80,15 +79,14 @@ public class StructuredOutputChatModelChain<Output: Decodable>: Chain {
                 stream: false
             ),
             stops: ["Observation:"],
-            promptTemplate: { input in
+            promptTemplate: promptTemplate ?? { input in
                 [
                     .init(
                         role: .system,
                         content: """
                         You are a helpful assistant
                         Generate a final answer to my query as concisely, helpfully and accurately as possible.
                         You don't ask me for additional information.
-                        \(extraSystemPrompt)
                         """
                     ),
                     .init(role: .user, content: input),