Cursor promises to do this[0] in the product, so, especially on HN, it'd be best to start with "why this is better than Cursor".
> favorite doc sites so I do not have to paste URLs into Cursor
This is especially confusing, because cursor has a feature for docs you want to scrape regularly.
This is different because of the background refresh, the identifier extraction and the graph. I know because I use cursor and am building the exact same thing oddly enough.
The goal here is not to replace Cursor’s own local codebase indexing. Cursor already does that part well. What Nia focuses on is external context. It lets agents pull in accurate information from remote sources like docs, packages, APIs, and broader knowledge bases