What type of queue item? 

A Service Request Processor has the ability to retain queued Service Requests.

There are System-Queue pyRetainOnFailure and pyRetainOnSuccess  properties.

Thanks Lee.

I'm referring to the normal queue item in System-Queue-DefaultEntry. 

Do we have any such configuration available for the Agents as well other than the Request Processors? 

In 8.X, Standard Agents are being replaced by Queue Processors.

I could say:  override System-Queue-DefaultEntry EstablishContext, set properties on the Primary page.

But in the long run you want to move away from using Standard Agents to using Queue Processors.

The reason for wanting to retain the record is that you want persisted information about successfully processed queued items, true?  All or a subset?

In the Activity that your Standard Agent class, why not log information somewhere else if making it through the activity without detecting an error?

Logging information about the processed events using the same standard agent makes much more sense Lee.. than having them piled up in the success queue.

Can we set the pyRetainonSuccess property by overriding the EstablishContext activity.

Is there any other place where we can set those properties? 

Not aware of any other way to set pyRetainonSuccess.

Not 100% certain below would work but you could try it.

Within System-Queue-DefaultEntry EstablishContext define pageName as a local variable in the Parameters tab, removing "String" in front of the statement that sets pageName.

      pageName = pageNames.getStringValue(i);   // String removed in front

In a second step set Param.PageName = local.pageName

In Pages & Classes define PageName as class @baseclass

Define an @baseclass True/False Property named "RetainOnSuccess".

In conjunction with calling Queue-For-Agent, set .RetainOnSuccess to true.  Doesn't matter if called immediately before or after.

In System-Queue-DefaultEntry EstablishContext, having PageName as the step page, define a When condition to check for .RetainOnSuccess = true.

If true, then set Primary.RetainOnSuccess = true.

In theory that would work..