Anyoen more familiar with Amazon Web Services than me (AWS) and know the 
answer to this?

Can I tell from my AWS API response if search inside the book is 
available? Is that information anywhere?

Right now, I'm calculating what the search inside the book URL _would_ 
be from the ASIN (which I get from the AWS), and then making a request 
to that url---and then screen-scraping for the phrase "temporarily 
unavailable" which is what they say if search inside the book doesn't 
exist. Sadly, they don't return 404 status in this case, they return 200 
status with that message.

But this is messy. And slows down my app, since I need to make a second 
http request to amazon. 

Anyone know if there's any way to predict it from the AWS response?

The AWS documentation and my actual in practice AWS response examples 
are both overwhelming and confusing me. :)