Incorrect response when adding wallet over USB connection

[jp1ac4]

Hello, I encountered this issue while debugging an issue in the Liana wallet (see https://github.com/wizardsardine/liana/issues/532 and https://github.com/wizardsardine/async-hwi/issues/34).

When adding a wallet to Specter DIY connected over USB, the response received from the Specter device in both Confirm and Cancel cases is "error: User cancelled", although in the Confirm case the Liana wallet is indeed added successfully to the Specter device.

We would like to use the response received from the Specter device to determine whether adding the Liana wallet succeeded or not.

Thank you.

[stepansnigirev]

It happens when the function that is processing the request returns None. It is the case for any request that doesn't require any data to be sent back to the host, like adding a wallet. I guess, I should do it slightly differently - response should be bool or a stream

• in case of bool we have True for success and False for user cancelled if no data is required. For USB communication it will translate to either a string ok or error: User cancelled.
• stream with data is returned if the user confirmed and we have some data to return to the host (i.e. signed psbt).