Atomic Swap APIs: Locking and Unlocking?

[michielpost]

I'm trying out the new Atomic Swap APIs, there is an API to get all locked UTXOs. It returns a list of Tx Ids that have locked UTXOs.

There is also an unlock api. This needs a partial tx as input to unlock.

It looks like there is a missing link somewhere. How do I get from the list of locked UTXOs to a partial tx ID so I can unlock them?
Maybe include the partial tx id that locks the UTXOs in the response?