The service description can be found in the OICP 2.1 (CPO).

Section:
3.4.1 eRoamingPushEVSEStatus

To download the latest OICP Version, please visit our website:
https://www.hubject.com/downloads/

In order to improve the efficency of the data exchange the Open InterCharge Protocol separates the mostly static (location etc.pp) information of an EVSE transmitted via EVSEDataRecords from the current (highly) dynamic status of an EVSE like available or occupied. Apart from that the PushEvseStatus command can be used analogous to the PushEvseData command.
The following EVSE status are well-defined:
•	Available The charging spot is available for charging.
•	Reserved The charging spot is reserved and not available for charging.
•	Occupied The charging spot is busy.
•	OutOfService The charging spot is out of service and not available for charging.
•	Unknown No status information available.

<soapenv:Envelope xmlns:soapenv    = "http://schemas.xmlsoap.org/soap/envelope/"
                  xmlns:EVSEStatus = "http://www.hubject.com/b2b/services/evsestatus/v2.0">

   <soapenv:Header/>

   <soapenv:Body>
      <EVSEStatus:eRoamingPushEvseStatus>
         <EVSEStatus:ActionType>fullLoad|update|insert|delete</EVSEStatus:ActionType>
         <EVSEStatus:OperatorEvseStatus>

            <EVSEStatus:OperatorID>DE*GEF</EVSEStatus:OperatorID>
            <!--Optional:-->
            <EVSEStatus:OperatorName>Test-CPO</EVSEStatus:OperatorName>

            <!--One or more repetitions:-->
            <EVSEStatus:EvseStatusRecord>
               <EVSEStatus:EvseId>DE*GEF*E1234*1</EVSEStatus:EvseId>
               <EVSEStatus:EvseStatus>Occupied</EVSEStatus:EvseStatus>
            </EVSEStatus:EvseStatusRecord>

         </EVSEStatus:OperatorEvseStatus>
      </EVSEStatus>
   </soapenv:Body>

</soapenv:Envelope>

<soapenv:Envelope xmlns:soapenv     = "http://schemas.xmlsoap.org/soap/envelope/"
                  xmlns:CommonTypes = "http://www.hubject.com/b2b/services/commontypes/v2.0">
    <soapenv:Body>
        <CommonTypes:eRoamingAcknowledgement>
            <CommonTypes:Result>true|false</CommonTypes:Result>
            <CommonTypes:StatusCode>
                <CommonTypes:Code>000</CommonTypes:Code>
                <CommonTypes:Description>Success</CommonTypes:Description>
                <CommonTypes:AdditionalInfo />
            </CommonTypes:StatusCode>
        </CommonTypes:eRoamingAcknowledgement>
    </soapenv:Body>
</soapenv:Envelope>