Visual Studio Code's Copilot Chat architecture enables extension authors to integrate with the GitHub Copilot Chat experience. A chat extension is a VS Code extension that uses the Chat extension API by contributing a Chat participant. Chat participants are domain experts that can answer user queries within a specific domain.
The Language Model API enables you to use the Language Model and integrate AI-powered features and natural language processing in your Visual Studio Code extension.
When an extension uses the Chat or the Language Model API, we call it a GitHub Copilot Extension, since GitHub Copilot is the provider of the Chat and the Language Model experience.
This sample shows two different ways to build a chat participant in VS Code:
See [simple.ts](src/simple.ts) for an example of a simple chat participant that makes requests and responds to user queries. It shows how you can create chat participants with or without the [@vscode/prompt-tsx](https://www.npmjs.com/package/@vscode/prompt-tsx) library.
See [toolParticipant.ts](src/toolParticipant.ts) for an example of a chat participant that invokes tools, either dynamically or using the `toolReferences` that are attached to the request. This is a more advanced example that shows how you can use the [@vscode/prompt-tsx](https://www.npmjs.com/package/@vscode/prompt-tsx) library to implement the LLM tool calling flow and tries to implement all the features of the chat API.