How can I find out who wrote the acceptance criteria so I can ask them some questions.
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The answer to that is dependent on where you are writing them.
If they are being added to fields on Jira issues, then you can look at the history of the issue to see who updated the fields (if no changes, then it was the person who created the issue!). Some people do acceptance criteria in linked Confluence pages. Again, the page will have a history, but it might not be very accurate for your needs, as Confluence will only reflect the person who saved the new version of the page (but they should know who they were working with on the page).
Or is it another system?
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