GitHub Copilot–Format your code using hooks

GitHub Copilot supports hooks that can automate tasks during an agent session. A practical use case is auto-formatting C# code after every file edit using the postToolUse hook event. The post walks through writing a PowerShell script that detects .cs file edits and runs dotnet format with .editorconfig rules, then configuring the hook JSON file in .github/hooks. It also explains why postToolUse is preferable to sessionEnd: the agent sees clean, formatted code before its next step, leading to better decisions and cleaner diffs.