Parameter added to business object tool header is not getting identified when called from agent

Summary:

We have a custom agent which uses business object to update assignment using PATCH operation. The Effective-Of parameter was added to the header and the parameter is identified as parameter in business object. But same tool when called with in agent , the header date parameter alone is not getting properly passed were as values for other parameters which were defined in the payload and the url path is getting passed properly. If the date is hard coded in the header, then the operation is submitted successfully.

Attached a document reference with screenshots.

Any insights on this?

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