# ChatGPT-API-unity A client library of [ChatGPT chat completion API](https://platform.openai.com/docs/api-reference/chat/create) for Unity. See also official [document](https://platform.openai.com/docs/guides/chat) and [API reference](https://platform.openai.com/docs/api-reference/chat). ## How to import by Unity Package Manager Add following dependencies to your `/Packages/mainfest.json`. ```json { "dependencies": { "com.mochineko.chatgpt-api": "https://github.com/mochi-neko/ChatGPT-API-unity.git?path=/Assets/Mochineko/ChatGPT_API#0.7.2", ... } } ``` ## How to use chat completion by ChatGPT API 1. Generate API key on [OpenAI](https://platform.openai.com/account/api-keys). (Take care your API key, this is a secret information then you should not open.) 2. You can specify chat model. (Available models are defined by `Model`.) 3. Create an instance of `ChatCompletionAPIConnection` with API key and chat model. (This instance memorizes old messages in session.) 4. You can set system message (prompt) to instruct assistant with your situation by constructor of `ChatCompletionAPIConnection`. 5. Input user message and call `ChatCompletionAPIConnection.CompleteChatAsync()`. 6. Response message is in `ChatCompletionResponseBody.ResultMessage` (= `ChatCompletionResponseBody.Choices[0].Message.Content`). An essential sample code with [UniTask](https://github.com/Cysharp/UniTask) is as follows: ```csharp #nullable enable using System; using System.Threading; using Cysharp.Threading.Tasks; using Mochineko.ChatGPT_API.Memories; using UnityEngine; namespace Mochineko.ChatGPT_API.Samples { ///

/// A sample component to complete chat by ChatGPT API on Unity. ///

public sealed class ChatCompletionSample : MonoBehaviour { ///

/// API key generated by OpenAPI. ///

[SerializeField] private string apiKey = string.Empty; ///

/// System message to instruct assistant. ///

[SerializeField, TextArea] private string systemMessage = string.Empty; ///

/// Message sent to ChatGPT API. ///

[SerializeField, TextArea] private string message = string.Empty; ///

/// Max number of chat memory of queue. ///

[SerializeField] private int maxMemoryCount = 20; private ChatCompletionAPIConnection? connection; private IChatMemory? memory; private void Start() { // API Key must be set. if (string.IsNullOrEmpty(apiKey)) { Debug.LogError("OpenAI API key must be set."); return; } memory = new FiniteQueueChatMemory(maxMemoryCount); // Create instance of ChatGPTConnection with specifying chat model. connection = new ChatCompletionAPIConnection( apiKey, memory, systemMessage); } [ContextMenu(nameof(SendChat))] public void SendChat() { SendChatAsync(this.GetCancellationTokenOnDestroy()).Forget(); } [ContextMenu(nameof(ClearChatMemory))] public void ClearChatMemory() { memory?.ClearAllMessages(); } private async UniTask SendChatAsync(CancellationToken cancellationToken) { // Validations if (connection == null) { Debug.LogError($"[ChatGPT_API.Samples] Connection is null."); return; } if (string.IsNullOrEmpty(message)) { Debug.LogError($"[ChatGPT_API.Samples] Chat content is empty."); return; } ChatCompletionResponseBody response; try { await UniTask.SwitchToThreadPool(); // Create message by ChatGPT chat completion API. response = await connection.CompleteChatAsync( message, cancellationToken); } catch (Exception e) { // Exceptions should be caught. Debug.LogException(e); return; } await UniTask.SwitchToMainThread(cancellationToken); // Log chat completion result. Debug.Log($"[ChatGPT_API.Samples] Result:\n{response.ResultMessage}"); } } } ``` See also [Sample](https://github.com/mochi-neko/ChatGPT-API-unity/raw/main/Assets/Mochineko/ChatGPT_API.Samples/ChatCompletionSample.cs). ## How to use chat completion by ChatGPT API more resilient See `RelentChatCompletionAPIConnection` and `RelentChatCompletionSample` using [Relent](https://github.com/mochi-neko/Relent). You can use API with explicit error handling, retry, timeout, bulkhead, and so on. ```json { "dependencies": { "com.mochineko.chatgpt-api.relent": "https://github.com/mochi-neko/ChatGPT-API-unity.git?path=/Assets/Mochineko/ChatGPT_API.Relent#0.7.2", "com.mochineko.chatgpt-api": "https://github.com/mochi-neko/ChatGPT-API-unity.git?path=/Assets/Mochineko/ChatGPT_API#0.7.2", "com.mochineko.relent": "https://github.com/mochi-neko/Relent.git?path=/Assets/Mochineko/Relent#0.2.0", "com.cysharp.unitask": "https://github.com/Cysharp/UniTask.git?path=src/UniTask/Assets/Plugins/UniTask", ... } } ``` ## How to calculate token length of text in local You can calculate token length of text by `TiktokenSharp.Tiktoken.Encode(string)` as follows: ```csharp using TiktokenSharp; private int CalculateTokenLength() { string text = "A text that you want to calculate token length."; // Specify model name. Tiktoken tiktoken = TikToken.EncodingForModel("gpt-3.5-turbo"); // Encoding is tokenizing. int[] tokens = tikToken.Encode(text); return tokens.Length; } ``` If you want to calculate on Unity editor, please use `ItemuMenu > Mochineko > TiktokenEditor` window. ## How to customize chat memories You can use customized memories of chat by implementing `IChatMemory` interface. Presets are available: - `FiniteQueueChatMemory` - A queue that has max number of messages. - `FiniteQueueWithFixedPromptsChatMemory` - A queue that has max number of user/assistant messages and free number of prompts (system messages). - `FiniteTokenLengthQueueChatMemory` - A queue that has max number of token lenght of all messages. - `FiniteTokenLengthQueueWithFixedPromptsChatMemory` - A queue that has max number of token lenght of user/assistant messages and free number of prompts (system messages). ## How to stream response See [streaming sample](https://github.com/mochi-neko/ChatGPT-API-unity/raw/main/Assets/Mochineko/ChatGPT_API.Samples/ChatCompletionAsStreamSample.cs). You can await foreach as follows: ```csharp var builder = new StringBuilder(); // Receive enumerable from ChatGPT chat completion API. var enumerable = await connection.CompleteChatAsStreamAsync( message, cancellationToken); await foreach (var chunk in enumerable.WithCancellation(cancellationToken)) { // First chunk has only "role" element. if (chunk.Choices[0].Delta.Content is null) { Debug.Log($"[ChatGPT_API.Samples] Role:{chunk.Choices[0].Delta.Role}."); continue; } var delta = chunk.Choices[0].Delta.Content; builder.Append(delta); Debug.Log($"[ChatGPT_API.Samples] Delta:{delta}, Current:{builder}"); } // Log chat completion result. Debug.Log($"[ChatGPT_API.Samples] Completed: \n{builder}"); ``` . ## How to use function calling 1. Define function with JSON schema. 2. Specify function by request parameters. 3. Call chat completion API. 4. Use `result.Choices[0].Message.FunctionCall` See `FunctionCalling()` in [test code](https://github.com/mochi-neko/ChatGPT-API-unity/raw/main/Assets/Mochineko/ChatGPT_API.Tests/ChatCompletionAPIConnectionTest.cs). ## Changelog See [CHANGELOG](https://github.com/mochi-neko/ChatGPT-API-unity/blob/main/CHANGELOG.md). ## 3rd Party Notices See [NOTICE](https://github.com/mochi-neko/ChatGPT-API-unity/blob/main/NOTICE.md). ## License Licensed under the [MIT](https://github.com/mochi-neko/ChatGPT-API-unity/raw/main/LICENSE) license.