Copilot's multi-file context is overrated. It reads your open tabs and guesses. For full-stack, you're constantly jumping between frontend components, API routes, and data models. Copilot's snippets get lost.
Cursor's "Project Index" is the difference. It builds a map of your entire codebase. You can ask about the `UserSchema` and it knows it's referenced in the auth middleware and the profile page component.
Example: Trying to add a new API endpoint.
* Copilot might suggest a route handler based on the current file.
* Cursor can infer you need to check the existing validation pattern from `utils/validation.js` and the error response format from `middleware/errors.js` because it's indexed them.
For real full-stack work, the tool needs to see the project, not just the recent files. Cursor does that. Copilot feels like a fancy autocomplete.
Simplicity is the ultimate sophistication