package.json - Extension manifest file declaring extension and command.
The sample plugin registers a command and defines its title and command name. With this information VS Code can show the command in the command palette. It doesn’t yet need to load the plugin.
src/extension.ts - Extension source code.
The file exports one function, activate, which is called the very first time your extension is activated (in this case by executing the command). Inside the activate function we call registerCommand.
We pass the function containing the implementation of the command as the second parameter to registerCommand.
.vscode/launch.json - Config for launching and debugging the vscode extension
.vscode/tasks.json - COnfig for build task that compiles TypeScript
Get up and running straight away
Press F5 to open a new window with your extension loaded.
Run your command from the command palette by pressing (Ctrl+Shift+P or Cmd+Shift+P on Mac) and typing Hello World.
Set breakpoints in your code inside src/extension.ts to debug your extension.
Find output from your extension in the debug console.
Make changes
You can relaunch the extension from the debug toolbar after changing code in src/extension.ts.
You can also reload (Ctrl+R or Cmd+R on Mac) the VS Code window with your extension to load your changes.