Data Validator - validate pipeline parameters?

Is there a way to validate the pipeline parameters using the data validator?
Getting the following error when trying to validate a pipeline parameter:

Data Validator[5dc15a412e2bfc322115a57d_286ad388-7bdb-4bcf-be8e-0cb286d68710 -- f2cdd56e-15b0-4ea4-a8a7-bf0d537584d2]
com.snaplogic.snap.api.SnapDataException: Error occurred while validating the document against the defined constraints
	at com.snaplogic.snaps.flow.DataValidator.getException(DataValidator.java:423)
	at com.snaplogic.snaps.flow.DataValidator.process(DataValidator.java:404)
	at com.snaplogic.snap.api.ExecutionUtil.process(ExecutionUtil.java:106)
	at com.snaplogic.snap.api.ExecutionUtil.executeForDocument(ExecutionUtil.java:118)
	at com.snaplogic.snap.api.ExecutionUtil.execute(ExecutionUtil.java:81)
	at com.snaplogic.snap.api.SimpleSnap.execute(SimpleSnap.java:70)
	at com.snaplogic.cc.snap.common.SnapRunnableImpl.executeSnap(SnapRunnableImpl.java:803)
	at com.snaplogic.cc.snap.common.SnapRunnableImpl.execute(SnapRunnableImpl.java:585)
	at com.snaplogic.cc.snap.common.SnapRunnableImpl.doRun(SnapRunnableImpl.java:868)
	at com.snaplogic.cc.snap.common.SnapRunnableImpl.call(SnapRunnableImpl.java:435)
	at com.snaplogic.cc.snap.common.SnapRunnableImpl.call(SnapRunnableImpl.java:117)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
	at java.base/java.lang.Thread.run(Thread.java:834)
Reason: Missing property value of $._opportunityId
Resolution: Address the reported issue.

Mapping this to a field beforehand defeats the purpose in this case, as I want to check whether this variable has been delivered.
Alternatively I could probably add an error view to a mapper and try mapping the parameters.

Best regards
Thomas