GitHub Copilot Chat extension goes open source in VS Code

Microsoft’s Visual Studio Code (VS Code) team has reached a key milestone in its vision to transform VS Code into an open‑source AI editor. On 30 June 2025, the team announced that the GitHub Copilot Chat extension has been released as open‑source software under the MIT licence.

By open‑sourcing this extension, Microsoft aims to harness community innovation and improve transparency in AI‑powered coding through collaboration and shared knowledge.

Why open‑source GitHub Copilot Chat

The primary motivations for this move are community‑driven innovation and data transparency. The VS Code team emphasises that as AI becomes central to software development, the supporting infrastructure must be built openly, mirroring the collaborative ethos that made VS Code successful over the last decade

By exposing the implementation of agent mode—including context handling, system prompts and telemetry—Microsoft grants developers full visibility into how the tool interacts with large language models (LLMs).

Explore, contribute and learn

Developers can now explore the full codebase of the Copilot Chat extension on GitHub. The open‑source release includes:

• Agent mode implementation details
• Context sent to LLMs
• Prompt‑engineering methodology
• Telemetry collection logic

Contributors can inspect these components to understand how AI agents operate within VS Code. They can also submit issues or pull requests to the central vscode repo as part of the long‑term plan to integrate Copilot Chat functionality into the VS Code core.

Furthermore, the team encourages developers to use the agent mode itself to navigate and analyse the codebase—demonstrating its utility as a learning and exploration tool.

What lies ahead

Moving forward, the VS Code team plans to refactor essential parts of the Copilot Chat extension into the core editor. While GitHub Copilot’s inline code completions remain closed‑source, their goal is to migrate that functionality into the open‑source Copilot Chat framework in upcoming months.

Microsoft is collaborating closely with the open‑source AI community to ensure use cases are well‑addressed and impactful. The focus remains on three pillars: performance, extensibility and user experience.

This transparency initiative invites developers and researchers to shape the future of AI‑powered code‑editing tools. Through shared code and collective feedback, Microsoft hopes to establish VS Code as a truly open‑source AI editor.