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Document: draft-ietf-oauth-device-flow-10
Reviewer: Robert Sparks
Review Date: 2018-06-11
IETF LC End Date: 2018-06-12
IESG Telechat date: Not scheduled for a telechat

Summary: Ready for publication as a Proposed Standard RFC, but with nits to consider

Nits/editorial comments: 

In 3.5 "the client MUST use a reasonable default polling interval" is not testable. Who determines "reasonable"? At the very least, you should add some text about how to determine what "reasonable" is for a given device, and add some text that says don't poll faster than earlier responses limited you to. For example, if the response at step B in the introductory diagram had an explicit interval of 15, but a slow-down response to an E message didn't have an explicit interval, you don't want them to default to, say 5 seconds (because that's what the example in section 3.2 said, so it must be reasonable).

In 3.3, you say the device_code MUST NOT be displayed or communicated. Is there a security property that's lost if there is? Or is this just saying "Don't waste space or the user's time"? 

The last paragraph of section 6.1 feels like a recipe for false positives, and for bug-entrenched code. Please reconsider it.

You need line-folding in the example in section 3.2