p:http-request 118 (NW)

The pipeline

<p:declare-step xmlns:c="http://www.w3.org/ns/xproc-step" xmlns:err="http://www.w3.org/ns/xproc-error" xmlns:p="http://www.w3.org/ns/xproc" xmlns:xs="http://www.w3.org/2001/XMLSchema" exclude-inline-prefixes="c xs" version="3.0">
   <p:output port="result"/>
   <p:option name="WHOST" select="'http://localhost:8246'" static="true"/>
   <p:http-request href="{$WHOST}/service/check-multipart" method="post" headers="map { 'content-type': 'multipart/alternative; boundary=--not-an-acceptable-boundary' }">
      <p:with-input>
         <p:inline>
            <doc1/>
         </p:inline>
         <p:inline>
            <doc2/>
         </p:inline>
      </p:with-input>
   </p:http-request>
</p:declare-step>