No DecodeResponse instance at runtime

[abigailalice]

I've seen the following error at runtime, and am not sure how to interpret it.

DecodeError: { error: UnhandledResponseError 'Could not decode response - no DecodeResponse instance'

I would assume any lacking instance should result in a compile time error, but this happens at runtime, returning a Left value when I try to contact my server. Wrapping the response in a record seems to consistently fix the issue, though I'm not sure why it's sometimes necessary.