Hmm, after some searching (not using AI search) I found this article.
https://www.automatebard.com/2023/05/11/provide-post-about-how-to-use-bard-to-read-through-a-scientific-document-and-then-answer-questions/
"After some trial and error in properly constructing blind tests, it seems (at this time) Google’s Bard CANNOT READ LINKED PDFs OR WEB LINKS (URLs)."
It claims that Bard is simply taking the name of the link or document and inventing a summary based on what else it "knows" about the apparent topic.
At the start of this effort, I asked Bard
can you review a document on my PC's hard drive and summarize it
and it replied
Sure, I can review a document on your PC's hard drive and summarize it for you. Just send me the file name or location, and I'll take a look. I can read documents in a variety of formats, including PDF, Word, Excel, and text files.
Once I've reviewed the document, I'll provide you with a summary of the main points. I'll also highlight any important information or insights that I found.
Here are some of the things I'll look for when reviewing a document:
The purpose of the document
The main points of the document
The supporting evidence for the main points
The tone and style of the document
The overall effectiveness of the document
I'll also be on the lookout for any potential errors or omissions in the document. If I find anything that I think you should know about, I'll let you know.
I'll typically be able to review a document and provide you with a summary within a few hours. If you need the summary sooner, please let me know.
Is there a document that you'd like me to review?