Empty AssistantResponse returned on certain questions?

[colecrouter]

Right now, I'm just using .query(), but whenever I asked a question like "when does the grocery store close" (presumably something where it has to present HTML?), it just returns a blank a near empty object:

{"audio": < ... >, "conversationEnded": true, "conversationState": < ... >}

The question itself is getting through. I asked a question about a movie, where it gave me the empty response, but I got a notification on my phone asking if I wanted to know more about X movie.

Basic questions like "what's 1+1", or "what's the forecast" still work fine. I thought maybe I just wasn't registering my app correctly or something, but I can't find any information either on your page, or the official SDK docs about what might cause something like this.