In the API documentation, I can see that it's possible to fetch all responses, but in my scenario, this isn't the most optimal solution. After the survey is completed, the "end URL" redirects the user to an external program, which, based on the received survey response ID, needs to fetch the answers through the API. What would be the best way to achieve this?

See api.limesurvey.org/classes/remotecontrol...hod_export_responses
iFromResponseID == iToResponseID == the Saved id

You can get the current id in the endurl with {SAVEDID}

I’ve gone through the documentation several times, but I missed this part.

Thanks for the tip!