Xcode Chat Proxy (Beta)

With Xcode Chat Proxy, you can

• Use the models, tools, RAGs, and other capabilities of Copilot for Xcode directly within the Xcode built-in chat interface.
• Use the models in Xcode agents.
• Use extra Xcode related MCP tools that are not provided by Xcode yet.

Beta

Please note that Xcode Chat Proxy is currently in Beta. Some features may not work as expected, and we appreciate your feedback to help us improve it.

If you have any ideas or encounter any issues, feel free to share them on our GitHub Discussions, or submit an issue on our GitHub Issues page.

Setting Up Xcode Chat Proxy for Agents

To set up Xcode agents, follow the following steps:

1. In Xcode, go to Xcode > Settings > Intelligence and click OpenAI.
2. Click Codex and enable it by entering random value in the API Key field. Xcode will download the Codex cli then.
3. Open Copilot for Xcode and navigate to the Features > Xcode Chat Proxy section.
4. Click Copy Codex Configurations and follow the instructions to set up the Codex cli to use Xcode Chat Proxy.

For Claude agents, you can only use the MCP tools for now. We will implement the proxy later.

Setting Up Xcode Chat Proxy for Chat

To set up Xcode Chat Proxy, follow these steps:

1. Setup the models and chat settings in Copilot for Xcode.
2. Open Copilot for Xcode and navigate to the Features > Xcode Chat Proxy section.
3. Choose a port and start the Xcode Chat Proxy server.
4. In Xcode, go to Xcode > Settings > Intelligence and click Add a Model Provider.
5. Select Locally Hosted, enter the exact same port as in Copilot for Xcode, and click Add.
6. Now, you can select the model from Copilot for Xcode in the Xcode chat interface!

Note

It’s fine to keep the Allow Tools toggle on or off since no tool is provided yet from Xcode to custom models. But we on the Copilot for Xcode side will provide some tools for the AI.

Using the Proxy in Agents

Currently, we only translate the requests from Xcode agents to Copilot for Xcode models. The tools and RAG features are not supported yet, and may not be implemented in the future. We recommend to use MCP tools in agents for better experience.

Using the Proxy in Chat

Inherited Xcode Features

When using Xcode Chat Proxy, the AI can still use the features provided by Xcode, such as:

• File search.
• Update the code in the editor.
• Create new files.

But these features are not tool based, and have some limitations due to their weird design, they may not work as expected all the time (but most of the time they work). These limitations also restrict how we can implement the tools. Wish Apple will improve them in the future.

Using the Models

Once added the server, you will be presented a list of models available in Copilot for Xcode. If you don’t see any model, please make sure:

• The ExtensionService is running.
• The Xcode Chat Proxy Server is running.

And click refresh.

When you create a new conversation in Xcode, you will be able to select these models.

Preferences

You can configure some preferences for Xcode Chat Proxy in the Features > Chat section in Copilot for Xcode. For example, configure it to always respond in a specific language.

Using Contexts (RAG)

No matter which model you are using, you can use the RAG features provided by Copilot for Xcode in the Xcode chat interface. You can add contexts by typing @context-name in the chat input, and the app will inject the context into the prompt.

The available contexts are:

Contexts	Description
@sense	Include the symbols referenced by the current file.
@web	Include the search result of the query as context.
@project	Include the project content as context. (keyword search based at the moment)
@gitstatus	Include the git status and diff as context.
@gitlog	Include the git log as context.
@clipboard	Include the clipboard content as context.
@debugarea	Include the debug area content as context.

Using Tools

Xcode does not provide any tools, other than a file search syntax, to custom models yet. However, Copilot for Xcode provides some tools that you can use in the Xcode chat interface.

To use a tool, you have to make sure the model supports tool-using, and turn on Supports Function Calling in the model settings in Copilot for Xcode.

Caution

Depending on the model you are using, the tool-using experience may vary. Some models may not use the tools until you explicitly ask them to do so. In the future we will provide better guidance and prompts to help the models use the tools more effectively.

The available tools are:

build_project, test_project

You can ask the AI to build the project. The AI will execute the build command and analyze the build errors to suggest fixes.

search_additional_documentation

You can ask the AI to answer your question based on the documentation. It will use this tool to lookup the documentation from the Xcode bundle and all your dependencies.

For example, you can ask “How to add liquid glass effect to a view?” and the AI will lookup the latest documentation inside the Xcode bundle and response with the .glassEffect API.

web_search, web_query

You can ask the AI to perform web search or query a web page by giving it urls. It will use the web search service and web page querying tool provided by Copilot for Xcode to get the information from the web.

query_search, find_files_by_path, symbol_search, read_file

You can turn on Use custom query tool to swap the default non-tool search with the tool based search. Tool-base search are usually more reliable.

Using Plugins

Enter /plugin-name in the chat input to use a plugin. The available plugins are:

Plugin	Description
/shell	Execute a shell command in the context of the current project.
/edit	Edit the selection in the active editor using the modification service.

The result will be presented in the chat interface as a code block. However, due to the limitation of Xcode chat interface, a code block won’t be rendered until it’s finished. So you may need to wait for a while if the command takes a long time to execute.

Using AGENTS.md

You can also provide project specific instructions to the AI by adding an AGENTS.md file to the root of your Xcode project. The content of the file will be appended to the system prompt.

Future Plans

We are actively working on improving the Xcode Chat Proxy experience. Here are some of the features we are planning to add in the future:

• UI to present the progress of tools and RAGs.
• More tools.
• MCP server.
• More MCP tools.
• Claude Code proxy.