Does it have some huge context window? Or is it really good at grep?

The Copilot version of this is just fucking terrible at suggesting anything remotely useful about our codebase.

I've had reasonable success just sticking single giant functions into context and asking Sonnet 4.5 targeted questions (is anything in this function modifying X, does this function appear to be doing Y) as a shortcut for reading through the whole thing or scattershot text search.

When I try to give it a whole file I actually hit single-query token limits.

But that's very "opt-in" on my part, and different from how I understand Cursor to work.