I’m responding to this tweet.
The short answer is no. FoldingText is a normal document based app (and it’s sandboxed) so it can’t search through your existing text files for todos. You could have an applescript to search for todo’s in your open documents, but I don’t think that’s what you are asking).
Does that sound like an approach that you or anyone else would be interested in? If so I can prioritize getting command line FoldingText a bit more documented.