How can I find xml schema of the sharing folder in the active sync requests?

I have a mailing app which is using active sync protocol. I can use command like sync, folderSync, itemOperations etc. but when I want to implement sharing a mailbox folder or a calendar folder there is no example of the request schema. I searched all of the active sync documentation but I could not find any mention of how can I implement.

Also when I try to test in microsoft active directory this schema sent for request:

<SharingMessage xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://schemas.microsoft.com/sharing/2008"> <DataType>calendar</DataType>

<Initiator>

<Name>Ben Miller</Name>

<SmtpAddress>*** Email address is removed for privacy ***</SmtpAddress>

<EntryId>00000000DCA740C8C042101AB4B908002B2FE18201000000000000002F6F3D4669727374204F7267616E697A6174696F6E2F6F753D45786368616E67652041646D696E6973747261746976652047726F7570202846594449424F484632335350444C54292F636E3D526563697069656E74732F636E3D42656E204D696C6C657200</EntryId>

</Initiator>

<Invitation>

<Providers>

<Provider Type="ms-exchange-internal" TargetRecipients="*** Email address is removed for privacy ***">

<FolderId xmlns="http://schemas.microsoft.com/exchange/sharing/2008">00000000BD4D6DECC5CFA5419E9CE1469EC14DD0010099AEA1C2B212FA4FB57226ED822C3035000000DE14740000</FolderId>

<MailboxId xmlns="http://schemas.microsoft.com/exchange/sharing/2008">0000000038A1BB1005E5101AA1BB08002B2A56C20000454D534D44422E444C4C00000000000000001B55FA20AA6611CD9BC800AA002FC45A0C000000534C432D44433031002F6F3D4669727374204F7267616E697A6174696F6E2F6F753D45786368616E67652041646D696E6973747261746976652047726F7570202846594449424F484632335350444C54292F636E3D526563697069656E74732F636E3D42656E204D696C6C657200</MailboxId>

</Provider>

</Providers>

</Invitation>

</SharingMessage>

But I do not know how to accept this request and after accepting request how to sync shared folder. Is anyone know how to do it?