The best solution to this kind of thing IMO may be to do an initial fast check to determine whether there may be a safety issue, then if there is show something

The best solution to this kind of thing IMO may be to do an initial fast check to determine whether there may be a safety issue, then if there is show something in the UI indicating the output will not be streamed but is loading. Then once the full output is available, evaluate it to determine whether it definitely is a safety risk to return it.