GitHub Copilot Chat is a conversational AI coding assistant available in supported integrated development environments (IDEs) and on GitHub.com that answers coding questions and proposes code changes with awareness of your open files and repository context.

Within editors such as Visual Studio Code, Visual Studio, and JetBrains IDEs, Copilot Chat can explain selected code, suggest fixes, and generate unit tests in an inline or dedicated chat view. It supports context controls like mentioning files or symbols and can operate in focused edit mode or agent mode for multi file updates and task style work, helping scaffold features, refactor code, and iterate on changes while you review and apply them.

Official website: docs.github.com/en/copilot/concepts/chat