Copy this workflow. Then copy the unique HTTP endpoint in your trigger step.

Then send an HTTP POST request to the endpoint with your XML file. The workflow will return a binary "valid" status if the XML parses correctly, or not.

λ ~/ curl -d @valid.xml https://myendpoint.m.pipedream.net
{"valid":true}                                                                                                                                       
λ ~/ curl -d @invalid.xml https://myendpoint.m.pipedream.net
{"valid":false}