I have a set of internal notes in a Perplexity Space and want to ask questions that stay grounded in those files. Sometimes the answer also appears to draw on material from the web, which makes it hard to tell whether the documents alone support a claim.

Is there a reliable way to ask Perplexity to use only the uploaded files for a response, or does a Space still combine file context with web search? I’m interested in how people verify which source a particular answer actually used.