The first thing that comes to mind would be somewhat manual, relying on the agents, but you could have a Wrap-up Code named something like "Resolved - First Contact" that the agents would assign to interactions that really are resolved at first contact. There are reports that show the wrap-up codes.
Otherwise, you can get data from the External Contacts feature (as long as every customer gets entered in the system when they call in), but there's no direct report you can run to see all the conversations and their results.
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George Ganahl GCP (PureCloud) ICCE CCXP
Principal Technology Consultant
Genesys
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