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Makes sense . I will dig in to this further. Am sure wayback provides this detail somewhere in it's api.

(yes, this is official documentation)

It's still in draft. likely to change. Also, it's for the save api, won't get the required info there.

Is there a more canonical url for that doc’s info? Also, is the CDX api the proper endpoint for Wayback provenance data?

Don't know. However, You can keep track of the issue here: https://github.com/vegetableman/vandal/issues/8